Pharmacology Midterms PDF

PHARMACOLOGY MIDTERMS _____________________________________________________________________________________ Phosphodiesterase Inhibitors (PDEI): Topics Outline: Examples: inamrinone lactate, milri...

PHARMACOLOGY MIDTERMS _____________________________________________________________________________________ Phosphodiesterase Inhibitors (PDEI): Topics Outline: Examples: inamrinone lactate, milrinone (administered IV). Cardiovascular System – Drugs and Uses: Primarily used for the short-term Diseases management of HF in patients who have not Drugs for Shock and Renal Failure responded to digoxin, diuretics, or Endocrine System – Drugs and Diseases vasodilators, or for long-term management in Nervous System – Drugs and Diseases patients awaiting heart transplant surgery. Mechanism of Action: These drugs increase intracellular cyclic adenosine monophosphate (cAMP), which enhances calcium influx and CARDIOVASCULAR SYSTEM thus strengthens myocardial contractility. OVERVIEW Adverse Reaction (ADR): Secondary The cardiovascular system comprises the thrombocytopenia, which is a reduction in heart, arteries, veins, and lymphatics. It is platelet count, is a notable adverse effect. responsible for transporting oxygen and essential nutrients to cells, removing metabolic waste products, and carrying hormones ANTIARRHYTHMIC DRUGS throughout the body. Antiarrhythmics are drugs used to treat arrhythmias, which are disturbances of the Drug Classes to Improve Cardiovascular normal heart rhythm. They are classified Function based on their mechanism of action. 1. Inotropic Drugs Classes of Antiarrhythmic Drugs: 2. Antiarrhythmic Drugs 3. Antianginal Drugs Class I (Sodium Channel Blockers): Largest 4. Antihypertensive Drugs group of antiarrhythmics; work by blocking 5. Diuretic Drugs sodium channels to control arrhythmias. 6. Antilipemic Drugs Divided into subtypes based on their specific actions. ○ Class IA: INOTROPIC DRUGS Mechanism: Alters myocardial cell membrane, Cardiac Glycosides slowing conduction and increasing the refractory Primary Agent: digoxin (considered the drug period. of choice or DOC). Examples: disopyramide Mechanism of Action: digoxin increases the phosphate, procainamide force of myocardial contraction, which hydrochloride, quinidine improves cardiac output (positive inotropic (available as sulfate and effect). Additionally, it slows the heart rate gluconate, which can cross (negative chronotropic effect) and decreases the blood-brain barrier; acidic electrical impulse conduction through the AV urine increases its excretion). node (negative dromotropic effect). ○ Class IB: Clinical Use: Commonly prescribed for heart Primary Use: Primarily treats failure (HF) and atrial fibrillation. acute ventricular arrhythmias by directly targeting Purkinje fibers and ventricular cells. Examples: lidocaine hydrochloride (IV, DOC in ABC | 1  acute care), mexiletine beta-blocker with additional Class III hydrochloride (also appears in properties). breast milk), tocainide ○ Mechanism: Prolongs the refractory hydrochloride. period and duration of the action Mechanism: Blocks rapid potential, helping to convert sodium influx during unidirectional blocks to bidirectional, depolarization-repolarization stabilizing electrical activity. phases, reducing arrhythmia Class IV (Calcium Channel Blockers): risk. ○ Examples: verapamil, diltiazem. Key Points: Class IB drugs ○ Uses: Effective in treating work by “going straight to the supraventricular arrhythmias that bottom of the heart” (Purkinje present with rapid ventricular fibers and ventricular response. myocardial cells). ○ Additional Agent: adenosine Toxicity: lidocaine toxicity can (injectable), used for paroxysmal lead to seizures and supraventricular tachycardia (PSVT). respiratory arrest. ○ Mechanism: Depresses pacemaker ○ Class IC: activity of the SA node, reducing HR, Use: Reserved for severe, and limiting AV node conduction. refractory ventricular ○ Note: Patients who consume caffeine arrhythmias resistant to other may require larger doses of adenosine treatments. due to antagonism by Examples: flecainide acetate, methylxanthines. moricizine, propafenone hydrochloride (excreted in stool; possesses ANTIANGINAL DRUGS beta-blocking properties, which may induce Angina treatment aims to reduce myocardial bronchospasm). oxygen demand or increase oxygen supply to Mechanism: Slows the heart. conduction without altering repolarization. Classes of Antianginal Drugs Class II (Beta-Adrenergic Antagonists or Beta-Blockers): 1. Nitrates: ○ Examples: acebutolol, esmolol (IV ○ Examples: nitroglycerin (DOC for only), propranolol (high lipid solubility, acute angina), amyl nitrite (inhalation), readily crosses the BBB). isosorbide dinitrate, isosorbide ○ Mechanism: Blocks beta-adrenergic mononitrate. receptors in the heart, slowing the ○ Forms: Sublingual, buccal, chewable, spontaneous firing of the SA node lingual aerosol, inhalation, (decreases automaticity), reducing the transdermal, and IV. strength of heart contractions, and ○ Mechanism: Relaxes smooth thereby lowering oxygen demand. muscles, dilating veins and reducing ○ Adverse Reactions: May cause preload (volume entering the arrhythmia, bradycardia, hypotension, ventricles), which decreases and bronchoconstriction. ventricular wall tension and oxygen ○ Drug Interactions: Increases risk of demand. By reducing afterload digoxin toxicity when taken with (arterial resistance), nitrates further esmolol. decrease oxygen requirements. Class III (Potassium Channel Blockers): ○ Adverse Reactions: Commonly ○ Uses: Primarily treats life-threatening causes headaches, hypotension, and ventricular arrhythmias. increased HR. ○ Examples: amiodarone ○ Drug Interactions: sildenafil should hydrochloride (DOC for emergency not be taken within 24 hours of nitrate ventricular tachycardia), dofetilide, administration due to the risk of severe ibutilide (IV), sotalol (a nonselective hypotension. 2. Beta-Adrenergic Blockers: ABC, SIM, J9 | 2  ○ Examples: atenolol, carvedilol (also ○ procainamide (Pronestyl): A sodium used for HF), metoprolol, nadolol, channel blocker that helps to decrease propranolol. heart excitability and conduction. ○ Use: Long-term prevention of angina; ○ verapamil (Calan): A CCB that helps blocks beta-adrenergic receptor sites control rapid ventricular response by in the heart muscle and conduction slowing conduction through the AV system, decreasing heart rate and node. force of contraction, thereby lowering oxygen demand. ASYSTOLE - Asystole, also known as ○ Drug Interactions: Absorption is "flatline," is the absence of electrical activity in delayed by antacids, hypotensive the heart, often resulting in cardiac arrest with effects are reduced by NSAIDs, and no detectable heartbeat. theophylline’s bronchodilation is Treatment Protocols: Advanced Cardiac Life impaired by nonselective Support (ACLS) is essential in asystole and beta-blockers. includes: 3. Calcium Channel Blockers: ○ Endotracheal intubation to secure the ○ Examples: amlodipine, diltiazem, airway. nicardipine, nifedipine, verapamil. ○ Transcutaneous pacing, if necessary. ○ Use: Primarily used to prevent angina Antiarrhythmic Medications: that does not respond to nitrates or ○ atropine: Increases heart rate by beta-blockers. Calcium channel inhibiting vagus nerve stimulation. blockers are particularly effective in ○ epinephrine (Adrenalin): Stimulates managing Prinzmetal’s angina. heart muscle activity, used to increase ○ Mechanism: Increases myocardial blood pressure and improve perfusion oxygen supply by dilating coronary in cardiac arrest. and peripheral arteries, while slowing the heart rate and reducing oxygen Ventricular Fibrillation (VFib) - Ventricular demand. fibrillation is a life-threatening heart rhythm that ○ Drug Interactions: verapamil and results in the heart's ventricles quivering instead diltiazem can increase the risk of of effectively pumping blood. digoxin toxicity and cause myocardial Medications for VFib According to ACLS depression. Protocols: ○ amiodarone (Cordarone): Used in cardiac arrest situations per ACLS ARRHYTHMIAS guidelines for VFib that is unresponsive to initial treatment. Atrial Fibrillation (AFib) - Atrial fibrillation is an ○ epinephrine (Adrenalin): Given to irregular heart rhythm that can lead to blood clots, stimulate cardiac muscle and improve stroke, heart failure, and other heart-related survival. complications. It occurs when the atria, the heart's ○ lidocaine (Xylocaine): Sodium upper chambers, beat irregularly, disrupting blood channel blocker used to stabilize the flow. heart rhythm in cases of VFib. Medications Used in AFib Management: ○ magnesium sulfate: Helps correct ○ amiodarone (Cordarone): A potent electrolyte imbalances that could antiarrhythmic drug that prolongs the precipitate or worsen VFib. action potential and refractory period, ○ procainamide (Pronestyl): Stabilizes thereby stabilizing heart rhythm. arrhythmias by reducing myocardial ○ digoxin (Lanoxin): Works by excitability. increasing the strength of heart ○ vasopressin (synthetic Pitressin): contractions and slowing the Often used per ACLS protocol to conduction through the AV node, support circulation during beneficial in rate control. resuscitation. ○ diltiazem (Cardizem): A calcium Watch Out For (WOF): Symptoms of channel blocker (CCB) that slows hypoperfusion, including hypotension, reduced heart rate by reducing electrical urine output (UO), and changes in level of conduction within the heart, used consciousness (LOC), which may indicate especially for ventricular rate control. inadequate circulation. ABC, SIM, J9 | 3  - These drugs inhibit the sympathetic nervous system (SNS) by various mechanisms, causing vasodilation or decreasing cardiac output to reduce BP. ARTERIAL OCCLUSIVE DISEASE Types and Mechanism of Action (MOA): ○ Central-Acting SNS Inhibitors: This condition is characterized by reduced blood clonidine HCl, methyldopa. flow due to blocked or narrowed arteries, often in ○ Alpha-Adrenergic Blockers: the legs, leading to pain, numbness, and doxazosin mesylate, phentolamine, increased risk of tissue ischemia. prazosin HCl, terazosin. Surgical Interventions: ○ Mixed Alpha and Beta-Adrenergic ○ Atherectomy: Procedure to remove Blockers: carvedilol, labetalol. plaque from the artery. ○ Norepinephrine Depletors: ○ Balloon Angioplasty: Expands the guanadrel sulfate, guanethidine artery to restore blood flow. monosulfate, reserpine. ○ Bypass Graft: Surgical creation of a Adverse Reactions (ADR): Hypotension, detour around the occluded area to dyspnea (DOB), blurred vision, restore circulation. bronchoconstriction, and orthostatic Pharmacologic Management: hypotension. ○ Thrombolytic Agents: Drug-Drug Interactions (DDI): alteplase (Activase): A tissue ○ carvedilol with antidiabetics may plasminogen activator (tPA) increase hypoglycemic effects. that dissolves blood clots. ○ clonidine with tricyclic antidepressants streptokinase (Streptase): (TCAs) may elevate BP. Another thrombolytic agent for ○ clonidine with CNS depressants may breaking down blood clots. worsen depression symptoms. ○ Heparin: Administered continuously via IV drip to prevent further clot 2. Vasodilating Drugs formation. - Vasodilators work by relaxing blood vessels, Nursing Considerations: reducing BP. CCBs prevent calcium from ○ For occlusions in the femoral and entering cells, producing arteriolar relaxation. popliteal arteries, assist with early Direct Vasodilators: ambulation but discourage prolonged ○ For Hypertensive Crisis: diazoxide, sitting to prevent further complications. nitroprusside. ○ For Resistant Hypertension: hydralazine HCl, minoxidil; typically ANTIHYPERTENSIVE DRUGS used in combination with other medications for severe hypertension. Hypertension, characterized by an elevated systolic and/or diastolic blood pressure, increases 3. ACE Inhibitors (ACEIs) the risk of cardiovascular complications. - ACE inhibitors are typically prescribed when beta blockers or diuretics are ineffective in Initial Therapy Options: managing hypertension. They lower blood ○ Diuretics and Calcium Channel pressure by interrupting the Blockers (CCBs): Common first-line renin-angiotensin-aldosterone system, which treatments, such as amlodipine, plays a key role in blood pressure regulation. diltiazem, nicardipine, and verapamil. Common ACE Inhibitors: ○ Other Drug Classes: Include ○ benazepril HCl sympatholytic drugs, vasodilators, ○ captopril: Known to potentially cause angiotensin-converting enzyme (ACE) proteinuria, rash, and loss of taste. inhibitors, and angiotensin II receptor ○ enalapril blockers (ARBs). ○ ramipril: Partially excreted in stool. ○ Combination Therapy: Often ○ enalaprilat: Administered prescribed to optimize BP control. intravenously (IV) for rapid effect in hypertensive emergencies. 1. Sympatholytic Drugs Mechanism of Action: ACE inhibitors work by disrupting the ABC, SIM, J9 | 4  renin-angiotensin-aldosterone system in the Important Patient Advice: following ways: ○ Avoid over-the-counter (OTC) or ○ Kidney Regulation of Blood herbal products without consulting a Pressure: Kidneys release the physician, as they may interfere with hormone renin in response to low ACE inhibitors’ effectiveness or blood pressure or reduced blood flow. exacerbate side effects. ○ Conversion Process: Renin acts on 4. Angiotensin II Receptor Blockers (ARBs) angiotensinogen, a plasma - ARBs are a class of antihypertensive protein, to form angiotensin I. medications that lower blood pressure by Angiotensin I is then blocking the vasoconstrictive effects of converted to angiotensin II, a angiotensin II. These drugs are often potent vasoconstrictor. prescribed as alternatives for patients who ○ Effects of Angiotensin II: cannot tolerate ACE inhibitors, as they It increases peripheral typically do not produce a persistent cough. resistance by narrowing blood Commonly Prescribed ARBs: vessels. ○ candesartan (Cilexetil) It promotes the release of ○ eprosartan aldosterone, a hormone that ○ losartan: Often used for its renal causes the kidneys to retain protective properties, especially in sodium and water, thereby patients with type 2 diabetes. increasing blood volume. ○ irbesartan: Similarly used to protect ○ How ACE Inhibitors Work: the kidneys in diabetic patients. ACE inhibitors block the ○ telmisartan conversion of angiotensin I to ○ valsartan: Commonly prescribed as angiotensin II, thus reducing an ACE inhibitor alternative, especially the levels of angiotensin II. for heart failure management. This results in the dilation of Mechanism of Action: arterioles, which decreases ○ ARBs work by preventing angiotensin peripheral vascular resistance II from binding to its receptors on and lowers blood pressure. blood vessels. This action blocks By reducing aldosterone angiotensin II’s ability to constrict secretion, ACE inhibitors blood vessels, leading to vessel promote sodium and water relaxation and a reduction in blood excretion, reducing blood pressure. volume and the workload on ○ Unlike ACE inhibitors, ARBs do not the heart. inhibit the conversion of angiotensin I Adverse Drug Reactions (ADR): to angiotensin II and do not interfere ○ Persistent cough (common with ACE with bradykinin (a vasodilator), which inhibitors) reduces the likelihood of a persistent ○ Angioedema (potentially cough. life-threatening) Adverse Drug Reactions (ADR): ○ Increased serum potassium ○ Common side effects include (hyperkalemia), especially when headache and fatigue. combined with potassium-sparing ○ May cause a dry cough or tickling diuretics sensation in the throat, though less ○ captopril may also cause protein in frequently than ACE inhibitors. the urine (proteinuria), rash, and loss ○ Angioedema (rare but serious) of taste. ○ Increased serum potassium Drug-Drug Interactions (DDI): (hyperkalemia) ○ ACE inhibitors combined with ○ Elevated blood urea nitrogen (BUN) potassium-sparing diuretics can lead and creatinine levels, indicating to hyperkalemia. potential effects on kidney function. ○ Avoid NSAIDs when using ACE Drug-Drug Interactions (DDI): inhibitors, as they may alter renal ○ losartan and fluconazole: This function and reduce the effectiveness combination may result in hypotension of ACE inhibitors. ABC, SIM, J9 | 5  due to increased blood levels of 2. Loop Diuretics losartan. ○ NSAIDs: These can reduce the Classification: High-ceiling, highly potent antihypertensive effects of ARBs, drugs producing the greatest volume of potentially diminishing their diuresis (urine production). effectiveness. Mechanism of Action: Act on the thick ○ rifampin: Increases the metabolism of ascending loop of Henle (part of nephron losartan, which can reduce its responsible for urine concentration) to antihypertensive effect.Bottom of Form increase the secretion of sodium, chloride, and water. They inhibit sodium, chloride, and water reabsorption. DIURETIC DRUGS Indications: ○ Treat edema in heart failure (HF). Used to promote the excretion of water and ○ Manage HTN, particularly to prevent electrolytes by the kidneys hypokalemia in potassium-sparing For HTN and cardiovascular conditions diuretics. ○ Thiazide ○ Treat edema related to liver disease or ○ Thiazide-like diuretics nephrotic syndrome. ○ Loop diuretics Examples: ○ Potassium-sparing diuretics ○ bumetanide (shortest acting) ○ ethacrynic acid ○ furosemide ○ torsemide 1. Thiazide and Thiazide-like Diuretics – Mechanism of Action for ARBs: Block the Sulfonamide derivatives binding of angiotensin II to the AT receptor, preventing angiotensin II from exerting its Cross the placental barrier and appear in vasoconstrictive properties and promoting breast milk aldosterone excretion, leading to lower BP. Mechanism of Action: Work by preventing DDI: Ototoxicity, hyperglycemia, lithium sodium from being reabsorbed by the kidneys. toxicity, and interactions with cardiac As sodium is excreted, it pulls water along with glycosides (which may trigger arrhythmias due it. to increased electrolyte imbalances). Examples: ○ benzthiazide 3. Potassium-Sparing Diuretics ○ chlorothiazide ○ hydrochlorothiazide Mechanism of Action: Weaker diuretics that ○ Thiazide-like diuretics: have the advantage of conserving potassium. chlorthalidone (90% bound to Examples: erythrocytes) ○ amiloride (not metabolized) Electrolyte Effects: Diuretics increase the ○ spironolactone (similar to aldosterone excretion of chloride, potassium, and antagonist) bicarbonate, which can result in electrolyte ○ triamterene imbalances. Indications: Long-term Use: Thiazides lower BP by ○ Treat edema, diuretic-induced causing arteriolar vasodilation. hypokalemia in HF, cirrhosis, nephrotic Specific Use: In patients with diabetes syndrome, and hypertension. insipidus, thiazides decrease urine volume ○ spironolactone is used to treat through sodium depletion and plasma-volume hyperaldosteronism and hirsutism reduction. (Stein-Leventhal polycystic ovary Most Common ADR: Reduced blood volume, syndrome). orthostatic hypotension (drop in BP upon Drug Interaction: Used with other diuretics to standing), hyponatremia, hypokalemia. potentiate their action or counteract Contraindications: Patients who are allergic potassium-wasting effects. to sulfonamide drugs. ADR: Risk of hyperkalemia, particularly when given with potassium supplements or high potassium diets. ABC, SIM, J9 | 6  activity of lipoprotein lipase, resulting in the breakdown of ANTILIPEMIC DRUGS triglycerides in lipoproteins, which leads to their clearance Antilipemic drugs are primarily used to lower from the bloodstream. abnormally high levels of lipids in the blood, Indications: Primarily used including cholesterol, triglycerides, and for the treatment of phospholipids. These medications are crucial for hypertriglyceridemia and to individuals at risk of coronary artery disease increase HDL cholesterol in (CAD). patients at risk for Lifestyle Modifications: Before or alongside cardiovascular disease. pharmacological treatment, patients are often ○ gemfibrozil: advised to implement lifestyle changes, Mechanism of Action: including dietary adjustments, weight loss, and gemfibrozil undergoes increased physical activity. extensive metabolism primarily in the liver and works by inhibiting the enzyme Classes of Antilipemic Drugs hepatic lipase, which increases the clearance of 1. Bile-Sequestering Agents triglyceride-rich lipoproteins ○ Examples: and enhances HDL ○ cholestyramine cholesterol levels. ○ colestipol hydrochloride Indications: It is particularly ○ colesevelam effective in reducing elevated ○ Mechanism of Action: These drugs triglyceride levels in patients are resins that bind bile acids in the with type IV and V intestine. By binding to bile acids, they hyperlipoproteinemia. prevent their reabsorption, leading to Pharmacodynamics: increased excretion of bile and a ○ These medications primarily exert their compensatory increase in bile acid effects through several mechanisms: synthesis from cholesterol, which Reduction of Cholesterol lowers LDL cholesterol levels. Production: They inhibit the ○ Pharmacokinetics: They remain in synthesis of apolipoproteins, the intestine, not absorbed from GIT, which are essential for the and are excreted in the stool. assembly and secretion of ○ Indications: These agents are triglyceride-rich lipoproteins. considered the drug of choice (DOC) Mobilization of Cholesterol for treating Type IIa from Tissues: They promote hyperlipoproteinemia (familial the release of stored hypercholesterolemia) in patients who cholesterol and triglycerides cannot adequately lower LDL levels from adipose tissue, through dietary means alone. facilitating their breakdown and utilization. 2. Fibric Acid Derivatives: Increased Cholesterol Excretion: Enhanced Definition: Fibric acid derivatives are a class excretion of cholesterol and of antilipemic agents derived from fungi, triglycerides via bile. primarily used to lower triglyceride levels and Decrease in Synthesis and increase high-density lipoprotein (HDL) Secretion of Lipoproteins: cholesterol levels. They decrease the hepatic Key Medications: production of very low-density ○ fenofibrate: lipoprotein (VLDL) and Mechanism of Action: low-density lipoprotein (LDL). fenofibrate is a prodrug that is Decrease in Synthesis of hydrolyzed to its active form, Triglycerides: They help fenofibric acid. This active lower triglyceride synthesis in metabolite enhances the ABC, SIM, J9 | 7  the liver by affecting fatty acid triglycerides in patient with type IV or synthesis pathways. V hyperlipidemia, at risk for pancreatitis, with hypercholesterolemia. 3. HMG-CoA Reductase Inhibitors ○ Used as antilipemic to boost HDL (Statins) levels. ○ Contraindications: Hypersensitivity to ○ Lower lipid levels by interfering with nicotinic acid, hepatic dysfunction, cholesterol synthesis. active peptic ulcer disease, or arterial ○ Examples: bleeding. atorvastatin calcium ○ Drug Interactions: May increase the fluvastatin sodium risk of myopathy, and its effectiveness lovastatin (requires liver can be diminished when taken with function tests) bile-sequestering drugs. Combining pravastatin with kava increases hepatotoxicity. simvastatin ○ Adverse Effects: Commonly causes ○ Mechanism of Action: Inhibit the vasodilation and flushing; this can be enzyme responsible for the conversion minimized by administering aspirin 30 of HMG-CoA to mevalonate, an early minutes prior or taking the step in the synthesis of cholesterol. extended-release form at night. ○ Indications: Used for primary hypercholesterolemia (Types IIa and 5. Cholesterol Absorption Inhibitors IIb) and to prevent cardiovascular ○ Examples: ezetimibe (considered the events like myocardial infarction (MI) DOC). and strokes. ○ Mechanism of Action: These agents ○ Drug Interactions: Caution is inhibit the intestinal absorption of required when combined with cholesterol and related phytosterols. clarithromycin, cyclosporine, and ○ Effects: It reduces blood cholesterol fluconazole due to the increased risk levels, leading to decrease in delivery of myopathy or rhabdomyolysis (fatal of intestinal cholesterol to liver, breakdown of skeletal muscle, causing reducing hepatic cholesterol and renal failure). increasing clearance from the blood. ○ Statins can also enhance the ○ Indications: Effective in treating anticoagulant effect of warfarin primary hypercholesterolemia and (Coumadin). homozygous sitosterolemia (hereditary ○ Administration Note: Statins should hyperabsorption of cholesterol and be given at least 1 hour before or 4 plant sterols), hours after bile-sequestering agents. ○ lower total cholesterol and LDL levels while increasing HDL. 4. Nicotinic Acid (Niacin) Drug-Drug Interactions (DDI): ○ Caution is required when prescribing ○ Characteristics: A water-soluble fibric acid derivatives with oral vitamin that has significant effects on anticoagulants (e.g., warfarin), as their lipid metabolism by decreasing use can significantly increase the risk triglyceride and apolipoprotein B-100 of bleeding. The anticoagulant effect levels while increasing HDL levels. may be potentiated due to ○ Forms: Available as displacement from protein binding immediate-release and sites or changes in metabolism. extended-release formulations. Clinical Considerations: ○ Mechanism of Action: It reduces ○ Patients should be monitored for liver hepatic synthesis of lipoproteins and function, especially when gemfibrozil inhibits the mobilization of free fatty is used alongside statins, as the acids from adipose tissue, leading to combination may further elevate the increased fecal elimination of sterols. risk of hepatotoxicity and myopathy. ○ Clinical Use: Often used in Adverse Effects: combination with other drugs to lower ○ Common side effects include gastrointestinal disturbances (such as ABC, SIM, J9 | 8  abdominal pain, diarrhea, and ○ Iron dextran (for parenteral use) nausea), muscle pain or weakness, ○ Sodium ferric gluconate complex and potential liver enzyme elevation. Absorption Sites: Primarily absorbed in the ○ Rare but serious side effects include duodenum and upper jejunum. For optimal rhabdomyolysis, particularly when absorption: combined with statins, necessitating ○ Enteric-Coated Preparations: Not vigilance for symptoms such as recommended as they bypass the unexplained muscle pain, weakness, duodenum, resulting in decreased or dark urine. absorption. Transport in Blood: Once absorbed, iron binds to transferrin, a plasma protein that HEMATOLOGIC DRUGS transports iron to various tissues. Iron Storage Sites: Stored as ferritin or Hematologic drugs are essential in treating hemosiderin in reticuloendothelial cells various blood disorders, targeting components of located in the liver, spleen, and bone blood such as plasma (liquid component of blood) marrow. and blood cells (RBC, WBC, and platelets). ○ Iron Distribution: About 66% of the These drugs are broadly classified into hematinic body’s iron is used in hemoglobin drugs, anticoagulant drugs, and thrombolytic production. drugs. ○ Breast Milk Presence: Iron also appears in breast milk, which helps HEMATINIC DRUGS prevent deficiency in infants. ➔ Purpose: Hematinic drugs provide essential Iron is essential for RBC production building blocks for red blood cell (RBC) (erythropoiesis) in the bone marrow. production. They increase hemoglobin It is directed to the bone marrow to support levels, necessary for oxygen transport new RBC synthesis. throughout the body. ➔ Types of Hematinic Drugs and Their Uses: ★ Target Populations for IDA (Iron Deficiency Iron Anemia) Prevention: Vitamin B12 Children (6 months to 2 years): Due to rapid Folic Acid growth, this age group benefits from iron Erythropoietin agents (specifically for supplementation to avoid IDA. treating normocytic anemia) Pregnant Women: Iron is critical for the ➔ Indications: developing fetus, necessitating additional Iron, Vitamin B12, and Folic Acid are supplementation. used to treat various forms of anemia: ○ Microcytic Anemia: Typically ★ Parenteral Iron Therapy treated with iron supplementation. ○ Macrocytic Anemia: Often treated - Parenteral iron is administered when oral iron is with Vitamin B12 and folic acid. ineffective or inappropriate, such as in cases of: Erythropoietin Agents: Used Malabsorption (e.g., ulcerative colitis, Crohn's specifically for normocytic anemia, disease) often due to chronic illness or renal End-stage renal disease (ESRD) requiring disease. hemodialysis. Common Forms and Administration of IRON THERAPY Parenteral Iron: ○ Iron Dextran: Can be given via Iron therapy is crucial in managing intramuscular (IM) injection or iron-deficiency anemia (IDA), the most common continuous intravenous (IV) infusion. anemia worldwide. ○ Iron Sucrose: Frequently used in Duration of Therapy: Iron therapy generally hemodialysis patients. requires 6 months to fully correct iron deficiency. ★ Drug Interactions with Iron Common Forms of Iron Supplements: ○ Ferrous fumarate - Certain substances and medications can reduce ○ Ferrous gluconate iron absorption: ○ Ferrous sulfate ABC, SIM, J9 | 9  Food and Beverages: Antacids, coffee, tea, FOLIC ACID THERAPY eggs, and milk. Medications: Tetracyclines, methyldopa, ★ Primary Use: Essential component for normal RBC levothyroxine, and penicillamine. production and growth. Folic acid is given to treat megaloblastic anemia due to insufficient dietary ★ Side Effects and Adverse Reactions of Iron intake, particularly in: Therapy Pregnancy: Essential to fetal development. Infancy and Childhood: Required for rapid Common Side Effects: Gastric irritation, growth and development. constipation, and darkened stools. Adverse Reaction: There is a risk of ★ Function of Folic Acid: anaphylaxis with parenteral iron, so an initial RBC Production and Growth: Vital for cell test dose is recommended before division and development of RBCs. administering a full infusion. Special Consideration for Liquid Iron: Liquid ★ Deficiency Indicators: iron may stain teeth, so it’s advised to use a Serum Levels: Serum folic acid below 5 straw or rinse the mouth after administration. ng/mL suggests deficiency. Folic Acid Derivative: Leucovorin Calcium VITAMIN B12 THERAPY may be used as an alternative in cases of deficiency or as adjunctive therapy. ★ Primary Use: Vitamin B12 is primarily used to treat pernicious anemia, a form of megaloblastic ERYTHROPOIETIN AGENTS anemia. ★ Common Forms of Vitamin B12 Supplements: - Erythropoietin agents are synthetic forms of a cyanocobalamin glycoprotein hormone that stimulate RBC hydroxocobalamin production (erythropoiesis) in the bone marrow. Available in oral, parenteral, and intranasal forms. ★ Types of Erythropoietin Agents ★ Mechanism and Function of Vitamin B12 Epoetin Alfa: Peaks in 5–24 hours with a Intrinsic Factor Requirement: B12 half-life of 4–13 hours. absorption requires intrinsic factor, which is Darbepoetin Alfa: Peaks in 24–72 hours with secreted by parietal cells of the gastric a half-life of 49 hours. mucosa. ★ Mechanism of Action Functions of Vitamin B12: Administration Routes: Erythropoietin agents ○ Cell Growth and Replication: Critical can be administered subcutaneously (SC) or for DNA synthesis. intravenously (IV). ○ Myelin (nerve coverings) Function in the Body: Normally, Maintenance: Essential for nerve erythropoietin production is a response to health. hypoxia (low oxygen levels). It is synthesized ○ Metabolism: Involved in lipid and in the kidneys and stimulates RBC production carbohydrate metabolism. to address oxygen deficiencies. Boost the ★ Pernicious Anemia production of erythropoietin, thus stimulating Description: A form of megaloblastic anemia RBC production in bone marrow. caused by a deficiency of intrinsic factor, ○ Normocytic Anemia: This type of leading to reduced B12 absorption. anemia is often due to chronic conditions such as kidney disease, o Intrinsic factor- secreted by parietal where erythropoietin production is cells of gastric mucosa essential for reduced. Treatment with erythropoietin vitamin B12 agents can correct anemia after 5–6 Common Causes: Often linked to gastric treatments. atrophy, partial or total gastrectomy, or total ★ Clinical Applications ileal resection. Primary Uses: Often used in chronic kidney ★ Drug Interactions (DDIs) with Vitamin B12 disease, anemia due to chemotherapy, and Absorption Inhibitors: Alcohol, aspirin, and other cases where natural erythropoietin levels colchicine can reduce B12 absorption. are inadequate to maintain normal RBC counts. ABC, SIM, J9 | 10  Laboratory Effects: During heparin therapy, ANTICOAGULANT DRUGS whole blood clotting time, thrombin time, and PTT are prolonged. Anticoagulant drugs are crucial in reducing blood clot formation, effectively managing conditions Clinical Uses: associated with high risk of thrombosis. They are categorized into several types: Prevents clotting during intra-abdominal or Heparin and its derivatives orthopedic surgeries. Oral anticoagulants Reduces clotting during extracorporeal Antiplatelet drugs circulation (e.g., cardiopulmonary bypass Direct thrombin inhibitors machines and hemodialysis). Factor Xa inhibitors Deep vein thrombosis (DVT) and pulmonary embolism (PE) prevention and treatment. Pharmacotherapeutics: 1. Heparin and Its Derivatives Prevent or treat venous thromboembolism: Overview: Heparin is an anticoagulant derived from This involves managing inappropriate or animal tissues, functioning as an antithrombotic excessive intravascular activation of blood agent. It prevents blood clots but cannot dissolve clotting. existing ones or affect clotting factor synthesis. Treating disseminated intravascular coagulation (DIC): A complication of various Types of Heparin: diseases that results in accelerated clotting. Treating arterial clotting: Prevents embolus Unfractionated Heparin (UFH) formation in patients experiencing an acute Low-Molecular-Weight Heparin (LMWH): myocardial infarction (MI). ○ Examples include dalteparin sodium, Extracorporeal Circulation: Heparin can be enoxaparin sodium, and tinzaparin used in machines like cardiopulmonary sodium. bypass machines or during hemodialysis ○ Primarily used to prevent deep vein procedures. thrombosis (DVT) in surgical patients. Drug Interactions (DDIs): Administration and Monitoring Enhanced anticoagulant effects when used with NSAIDs, iron dextran, clopidogrel, Routes of Administration: Given parenterally aspirin, and dipyridamole. (IV or SC). Warfarin combined with heparin can increase ○ UFH is administered through a bleeding risk, so monitoring is essential. continuous IV infusion and requires close monitoring of Partial Adverse Reactions (ADRs): Thromboplastin Time (PTT). ○ LMWH has a longer circulating Bleeding: Treatable with protamine sulfate, half-life, allowing for once-daily (OD) which binds to heparin, forming a stable salt. or twice-daily (BID) SC injections. Other ADRs include bruising, hematoma Note: LMWH should not be formation, skin necrosis, and given intramuscularly (IM) due thrombocytopenia. to the risk of localized bleeding. 2. Oral Anticoagulants Mechanism of Action Primary Agent: warfarin sodium (a coumarin derivative) Function: Heparin prevents the formation of new thrombi by inhibiting thrombin and fibrin Mechanism of Action: formation. It activates antithrombin III, which subsequently neutralizes thrombin. warfarin inhibits the liver’s ability to synthesize Vitamin K-dependent clotting factors ABC, SIM, J9 | 11  (including prothrombin, VII, IX, and X), ○ Aspirin maintains effects for 10 days leading to reduced clotting potential. (platelet lifespan) but shows onset within 15–20 minutes and lasts 6–8 Absorption and Metabolism: hours after administration. Pharmacodynamics: Oral Absorption: Warfarin is quickly ○ Low-dose aspirin inhibits absorbed, binds to plasma albumin, and is prostaglandin synthesis, blocking metabolized in the liver, with excretion through thromboxane A2 formation and, thus, urine. platelet aggregation. Onset and Duration: Takes about 48 hours ○ Clopidogrel inhibits platelet for initial effects and 3–4 days to reach full aggregation by blocking effect. Regular monitoring of Prothrombin platelet-fibrinogen binding. Time (PT) and International Normalized Ratio (INR) is necessary. Clinical Uses Therapeutic Uses: aspirin: Reduces death risk in men with transient ischemic attacks (TIAs) and Prevention of thromboembolism in patients reduces systemic embolism in conditions like with DVT, prosthetic heart valves, diseased mitral stenosis. mitral valves, and high-risk thromboembolism clopidogrel: Reduces stroke risk, helps patients. manage acute coronary syndromes, and Often combined with antiplatelet drugs like supports patients undergoing procedures like aspirin, clopidogrel, or dipyridamole to PTCA or CABG. reduce arterial clot risk. eptifibatide: Administered during percutaneous coronary intervention (PCI). Drug Interactions (DDIs): dipyridamole: Often combined with warfarin post-cardiac valve replacement or with aspirin Increased bleeding risk with acute alcohol use. post-CABG. Vitamin K-rich diets and fresh frozen plasma (FFP) can reduce warfarin’s efficacy. Drug Interactions (DDIs): Adverse Reactions (ADRs): Increased bleeding risk when combined with NSAIDs, heparin, or other oral anticoagulants. Minor bleeding, hematoma formation, and cimetidine increases risk of ticlopidine risk of necrosis or gangrene in severe cases. toxicity. Antidote: Phytonadione (Vitamin K1) or FFP to reverse warfarin effects. Adverse Reactions (ADRs): 3. Antiplatelet Drugs ticlopidine can cause bleeding and should be discontinued before other anticoagulants. Antiplatelet drugs are designed to prevent arterial Some drugs (e.g., sulfinpyrazone) interact thromboembolism and reduce risk in patients with with aspirin, methotrexate, and valproic acid, conditions like myocardial infarction (MI), stroke, affecting plasma levels. and arteriosclerosis. 4. Direct Thrombin Inhibitors (DTIs) Common Drugs: Direct thrombin inhibitors block all thrombin activity, Oral Antiplatelet Drugs: aspirin, clopidogrel, preventing clot formation. dipyridamole, sulfinpyrazone, and ticlopidine. IV Antiplatelet Drugs: abciximab, eptifibatide, Examples: and tirofiban. argatroban Pharmacokinetics and Pharmacodynamics bivalirudin lepirudin Pharmacokinetics: Most antiplatelet drugs reach peak plasma levels in 1–2 hours. ABC, SIM, J9 | 12 Administration: DTIs are generally administered via ○ reteplase continuous IV infusion or intra-coronary bolus ○ streptokinase during cardiac catheterization. ○ tenecteplase ○ urokinase Pharmacokinetics: Mechanism of Action Onset: Begins within 2 minutes in cardiac procedures, peaking at 15 minutes with a Administration and Distribution: 2-hour duration. Thrombolytic drugs are administered Plasma Peaks: After SC injection, levels peak intravenously (IV) or intracoronary. Upon within an hour. entering the circulation, they quickly activate PTT Effects: Apparent within 4–5 hours; plasminogen, a precursor enzyme that platelet count recovery within 3 days. converts to plasmin—the enzyme responsible for dissolving fibrin clots. Clinical Uses: Streptokinase Clearance: Streptokinase is rapidly removed from circulation by Treats heparin-induced thrombocytopenia antibodies and the reticuloendothelial (HIT). system—a system involved in defending Bivalirudin is used for unstable angina during against infections and disposing of cellular PTCA (with aspirin). breakdown products. Placental Barrier: Thrombolytic drugs Special Considerations: generally do not cross the placental barrier, making them safer in certain patient Adjust dose for liver and kidney impairment. populations. Caution for those with high hemorrhage risk or Plasmin Activation: The primary action of undergoing procedures like spinal thrombolytic drugs is to convert plasminogen anesthesia. to plasmin, an enzyme that effectively lyses (dissolves) thrombi, fibrinogen, and other Drug Interactions (DDIs): plasma proteins that contribute to clot formation. warfarin with argatroban increases INR. Discontinue all parenteral anticoagulants Clinical Uses before administering argatroban. Treatment of Thrombolytic Disorders: 5. Factor Xa Inhibitor Drugs ○ Acute Myocardial Infarction (MI): Administered to dissolve clots that Primary Agent: fondaparinux (approved in the USA) obstruct coronary arteries and restore blood flow to the heart muscle. Mechanism of Action: Factor Xa inhibitors prevent ○ Ischemic Stroke: Used to break down DVT by binding to antithrombin III and neutralizing clots in cerebral arteries, improving factor Xa, thus inhibiting the coagulation cascade and blood flow to the brain and potentially reducing clot formation. limiting brain damage. ○ Peripheral Artery Occlusion: Administration: Given subcutaneously. Employed to dissolve clots in Clinical Use: Primarily used to prevent blood clot peripheral arteries that may be formation, especially in patients undergoing total hip causing localized ischemia. or knee replacement surgery. Dissolution of Thrombi in Medical Equipment: ○ Arteriovenous Cannulas: Used to THROMBOLYTIC DRUGS clear clots in cannulas during dialysis. ○ IV Catheters: Thrombolytic drugs can Purpose: Thrombolytic drugs are used to help establish blood flow in IV lines by dissolve pre-existing clots or thrombi, primarily dissolving any obstructive thrombi. in acute or emergency situations where Preferred Agent for Newly Formed rapid clot breakdown is necessary. Thrombi: Thrombolytic drugs are the drug of Common Agents: choice (DOC) for breaking down newly ○ alteplase formed clots, and their effectiveness is ABC, SIM, J9 | 13  greatest when given within 6 hours of 1. Drug Class: Bile Acid Binding Resins symptom onset. ○ Drugs: cholestyramine, colestipol, colesevelam Reversal and Inhibition ○ Action: These drugs bind to bile acids in the intestines, which prompts the Aminocaproic Acid: This agent is used to liver to use cholesterol to make more inhibit the action of streptokinase and can bile acids, thus lowering LDL reverse its fibrinolytic effects if excessive cholesterol. bleeding occurs. ○ Uses: Reduces LDL cholesterol levels in patients with hypercholesterolemia. Adverse Drug Reactions (ADR) ○ Therapeutic Outcome: Decreased LDL and total cholesterol levels, Bleeding: Thrombolytic drugs carry a helping prevent cardiovascular events. significant risk of bleeding, which may occur ○ Nursing Implications: Administer internally or at sites of recent surgical with food; monitor for side effects like incisions. constipation and GI discomfort. Allergic Responses: Patients may Encourage increased fluid intake and experience allergic reactions, especially with high-fiber diet to ease constipation. streptokinase, which may cause immune 2. Drug Class: Niacin (Nicotinic Acid, responses due to its foreign protein origin. Vitamin B3) ○ Drug: Niacin CARDIOVASCULAR DRUGS AND DISEASES ○ Action: Niacin reduces the liver’s OVERVIEW production of LDL and triglycerides, while increasing HDL cholesterol. Cardiovascular diseases (CVDs) affect the heart ○ Uses: Lowers LDL and triglycerides, and blood vessels, causing high rates of raises HDL in patients with morbidity and mortality. This category includes dyslipidemia. conditions like arrhythmias, congestive heart ○ Therapeutic Outcome: Balanced lipid failure, myocardial infarction, angina, profile with lower LDL and triglycerides hypertension, and hyperlipidemia, which often and higher HDL levels. stem from modifiable factors such as lifestyle ○ Nursing Implications: Watch for habits. Pharmacologic treatments play a crucial flushing, a common side effect; assess role in managing these conditions, including liver function periodically. Educate antiarrhythmics, antianginals, antihypertensives, patients to avoid alcohol and hot and antihyperlipidemic drugs. drinks with this medication to minimize Cardiovascular disease refers to various flushing. disorders involving the heart, arteries, and veins, 3. Drug Class: HMG-CoA Reductase often leading to serious outcomes like Inhibitors (Statins) myocardial infarction (MI), stroke, or heart ○ Drugs: atorvastatin, fluvastatin, failure. Risk factors include both lifestyle and rosuvastatin, simvastatin genetic components such as family history, ○ Action: Inhibits the enzyme involved obesity, and sedentary habits. in cholesterol production in the liver, CAD (Coronary Artery Disease), which refers to lowering cholesterol levels. the narrowing or obstruction of heart arteries. ○ Uses: Lowers LDL cholesterol and atherosclerosis (fatty deposits in arteries) slightly raises HDL levels; first-line hyperlipidemia (high cholesterol and agents for reducing cardiovascular triglycerides) risk. ○ Therapeutic Outcome: Reduced cholesterol levels, leading to reduced risk of heart attacks and strokes. I. Antihyperlipidemic Drugs ○ Nursing Implications: Administer statins at bedtime when cholesterol Used to reduce elevated blood cholesterol and synthesis is highest; monitor for triglyceride levels, these drugs play a key role in muscle pain, liver function, and any preventing atherosclerosis, heart attacks, and strokes. signs of rhabdomyolysis. ABC, SIM, J9 | 14  4. Drug Class: Fibric Acid Derivatives Uses: Effective for severe ○ Drugs: gemfibrozil, fenofibrate hypertension or heart failure. ○ Action: Primarily lowers triglyceride Nursing Implications: levels and modestly increases HDL Monitor potassium levels levels. closely; risk of dehydration ○ Uses: Used in patients with high and electrolyte depletion. triglycerides or combined dyslipidemia. ○ Potassium-Sparing Diuretics ○ Therapeutic Outcome: Reduced risk Drugs: spironolactone, of pancreatitis associated with high amiloride triglycerides. Uses: Often used with other ○ Nursing Implications: Administer diuretics to prevent potassium with food to increase absorption; loss. monitor for GI upset, liver function, Nursing Implications: and gallstones. Monitor potassium levels to 5. Drug Class: Miscellaneous Antilipemic prevent hyperkalemia. Agents 2. Beta-Blockers ○ Drug: ezetimibe (Zetia) ○ Drugs: atenolol, metoprolol, ○ Action: Acts on the small intestine to propranolol inhibit cholesterol absorption from diet ○ Action: Reduce heart rate and and bile. decrease cardiac output by blocking ○ Uses: Used alone or with statins to beta receptors. further lower cholesterol levels. ○ Uses: Treatment of hypertension, ○ Therapeutic Outcome: Enhanced angina, and arrhythmias. cholesterol reduction, particularly ○ Nursing Implications: Monitor heart useful in combination therapy. rate and blood pressure before each ○ Nursing Implications: Monitor for GI dose; use cautiously in patients with side effects; educate the patient to respiratory conditions like asthma. maintain dietary modifications to 3. ACE Inhibitors optimize results. ○ Drugs: lisinopril, enalapril, ramipril ○ Action: Inhibits angiotensin-converting enzyme, relaxing blood vessels. ○ Uses: Effective in hypertension, heart II. Antihypertensive Drugs failure, and kidney protection in diabetic patients. Medications that lower high blood pressure, reducing ○ Nursing Implications: Watch for a the risk of stroke, myocardial infarction, and other persistent dry cough and angioedema; complications. monitor renal function and avoid use in pregnancy. 1. Diuretics 4. Angiotensin II Receptor Blockers ○ Purpose: Reduce blood volume (ARBs) through increased urine production, ○ Drugs: losartan, valsartan lowering blood pressure. ○ Action: Blocks angiotensin II, relaxing ○ Thiazide Diuretics blood vessels. Drugs: hydrochlorothiazide, ○ Uses: Similar to ACE inhibitors, used chlorthalidone in patients intolerant of ACE inhibitors. Uses: First-line treatment for ○ Nursing Implications: Monitor blood hypertension. pressure and kidney function; check Nursing Implications: for dizziness or hypotension. Monitor for electrolyte 5. Calcium Channel Blockers imbalances and dehydration; ○ Drugs: amlodipine, diltiazem, encourage potassium-rich verapamil foods. ○ Action: Relaxes blood vessels and ○ Loop Diuretics reduces heart workload. Drugs: furosemide, ○ Uses: Effective for hypertension, bumetanide angina, and certain arrhythmias. ABC, SIM, J9 | 15  ○ Nursing Implications: Watch for 2. Beta-Blockers and Calcium Channel swelling, dizziness, and avoid Blockers grapefruit juice with these drugs. ○ Uses: Reduce heart workload in angina. ○ Nursing Implications: Beta-blockers should be avoided in asthma; monitor III. Antiarrhythmic Drugs blood pressure and heart rate. Used to treat abnormal heart rhythms by stabilizing the heart's electrical conduction pathways. ANTIHYPERTENSIVE DRUGS AND HYPERTENSION MANAGEMENT 1. Class I - Sodium Channel Blockers ○ Drugs: quinidine, procainamide, Hypertension, or high blood pressure (BP), lidocaine is characterized by elevated systolic and/or ○ Action: Slows electrical conduction in diastolic blood pressure, leading to risks like the heart, stabilizing rhythm. heart attack, stroke, and premature death. It is ○ Nursing Implications: Monitor ECG; measured in mmHg and includes both check for toxicity signs. systolic (pressure when the heart pumps) and 2. Class II - Beta-Blockers diastolic (pressure when the heart relaxes) ○ Drugs: propranolol, esmolol readings. ○ Action: Reduces heart rate and Pulse pressure (PP) is the difference strength of contraction. between systolic and diastolic BP and reflects ○ Nursing Implications: Check vital arterial tone, while mean arterial pressure signs; avoid abrupt discontinuation. (MAP) is the average pressure over one 3. Class III - Potassium Channel Blockers heartbeat cycle. ○ Drugs: amiodarone, sotalol Blood pressure is a product of cardiac output ○ Action: Extends repolarization, (CO) and peripheral vascular resistance stabilizing heart rhythm. (PVR), with CO determining systolic and PVR ○ Nursing Implications: Requires diastolic pressures. monitoring of pulmonary and thyroid For hypertension, defined as BP > 140/90 function; frequent ECG monitoring mmHg, treatment includes lifestyle recommended. modifications, such as the DASH diet, salt and 4. Class IV - Calcium Channel Blockers alcohol reduction, weight control, stress ○ Drugs: verapamil, diltiazem management, and adequate sleep. ○ Action: Controls heart rhythm by slowing AV node conduction. ○ Nursing Implications: Monitor for bradycardia and hypotension. I. Diuretics Diuretics are often the first line of defense in managing hypertension as they decrease blood volume by IV. Antianginal Drugs promoting sodium and water excretion, leading to reduced blood pressure and peripheral vasodilation. Used to relieve chest pain due to decreased blood flow to the heart muscle. 1. Carbonic Anhydrase Inhibitors ○ Drug: acetazolamide (Diamox) 1. Nitrates ○ Action: Inhibits carbonic anhydrase, ○ Drugs: nitroglycerin, isosorbide leading to bicarbonate excretion and dinitrate mild diuresis. ○ Action: Dilates coronary arteries, ○ Uses: Mild effect on blood pressure; increasing oxygen supply to the heart. more often used for glaucoma or ○ Nursing Implications: Educate about altitude sickness. proper administration (e.g., sublingual ○ Nursing Implications: Monitor for quick relief); monitor for headache electrolyte levels, as it may cause and orthostatic hypotension. hypokalemia. 2. Thiazide and Thiazide-like Diuretics ○ Drug: Hydrochlorothiazide (Esidrix) ABC, SIM, J9 | 16  ○ Action: Reduces blood volume by III. Angiotensin-Converting Enzyme (ACE) inhibiting sodium reabsorption in distal Inhibitors tubules. ○ Uses: Primary choice for mild to ACE inhibitors reduce blood pressure by inhibiting the moderate hypertension. enzyme that converts angiotensin I to angiotensin II, a ○ Nursing Implications: Monitor potent vasoconstrictor. electrolyte levels, especially potassium; encourage potassium-rich Drugs: enalapril, lisinopril, captopril diet to prevent hypokalemia. Action: Decreases blood pressure by 3. Loop Diuretics reducing peripheral resistance and increasing ○ Drug: Furosemide (Lasix) artery elasticity. ○ Action: Inhibits sodium and chloride Uses: Effective in hypertension, especially in reabsorption in the loop of Henle, diabetic or heart failure patients. causing significant diuresis. Nursing Implications: Monitor for cough ○ Uses: Effective for hypertension with (common side effect) and orthostatic renal impairment. hypotension, particularly in older adults. ○ Nursing Implications: Monitor for dehydration and electrolyte IV. Angiotensin II Receptor Blockers imbalances, especially potassium. (ARBs) 4. Potassium-Sparing Diuretics ○ Drugs: Amiloride (Midamor), ARBs block angiotensin II receptors, preventing Spironolactone (Aldactone) vasoconstriction without causing a cough. ○ Action: Inhibits sodium reabsorption in the distal tubule without depleting Drugs: candesartan, eprosartan, olmesartan, potassium. telmisartan ○ Uses: Often combined with other Action: Blocks angiotensin II receptors, diuretics to maintain potassium levels. reducing peripheral vascular resistance. ○ Nursing Implications: Monitor Uses: Effective in patients who cannot tolerate potassium levels for hyperkalemia. ACE inhibitors. 5. Osmotic Diuretics Nursing Implications: Monitor for dizziness ○ Drug: Mannitol (Osmitrol) and hypotension; educate on orthostatic ○ Action: Draws water into the urine by safety. increasing osmotic pressure in renal tubules. V. Direct Renin Inhibitors ○ Uses: Primarily used for cerebral edema, not common for hypertension. Direct renin inhibitors block the first step in the ○ Nursing Implications: Monitor for renin-angiotensin-aldosterone system (RAAS), dehydration and electrolyte imbalance. preventing hypertension. II. Beta-Adrenergic Blocking Agents Drug: aliskiren (Tekturna) (Beta-Blockers) Action: Inhibits renin, reducing angiotensin II production and thus lowering blood pressure. Beta-blockers decrease heart rate, myocardial Uses: Reduces blood pressure in patients with contractility, and oxygen demand by blocking beta-1 high renin activity. receptors, lowering BP. Nursing Implications: Monitor for side effects like dizziness; avoid using in patients with Drugs: atenolol (Tenormin), propranolol renal impairment. (Inderal), metoprolol (Lopressor) Action: Decreases cardiac output and VI. Aldosterone Receptor Antagonists reduces heart rate, effectively lowering blood pressure. Aldosterone antagonists block aldosterone receptors, Uses: Commonly prescribed for hypertension, reducing sodium reabsorption and blood pressure. arrhythmias, and angina. Nursing Implications: Monitor heart rate and Drug: Eplerenone (Inspra) blood pressure; avoid abrupt discontinuation to Action: Inhibits aldosterone, decreasing prevent rebound hypertension. sodium and water retention. ABC, SIM, J9 | 17  Uses: Treats hypertension and heart failure. pressure and advise patients to rise slowly to Nursing Implications: Monitor potassium prevent orthostatic hypotension. levels; contraindicated if potassium >5.5 mEq/L. IX. Central Acting Alpha Agonists VII. Calcium Channel Blockers (CCBs) These agents reduce blood pressure by acting on the central nervous system to decrease sympathetic Calcium channel blockers inhibit calcium influx in outflow. vascular smooth muscle and cardiac cells, which leads to vasodilation, reduced peripheral resistance, and Drugs: clonidine (Catapres), methyldopa lower blood pressure. They are divided into two main Action: Decreases sympathetic activity, classes based on their primary effects and selectivity: lowering blood pressure. Uses: Used for resistant hypertension. 1. dihydropyridines (DHPs) Nursing Implications: Monitor for drowsiness ○ Drugs: amlodipine (Norvasc), and dry mouth; taper off gradually to avoid nicardipine (Cardene), nifedipine rebound hypertension. (Procardia) ○ Action: Primarily act on vascular X. Direct Vasodilators smooth muscle, causing vasodilation and lowering blood pressure with Direct vasodilators act by relaxing vascular smooth minimal effects on heart rate. muscle, particularly in arterioles, reducing blood ○ Uses: Effective for hypertension and pressure. angina. ○ Nursing Implications: Monitor for 1. hydralazine hypotension, peripheral edema, and ○ Uses: Treats stage 2 hypertension, flushing. Avoid grapefruit juice, as it especially in renal disease and can increase drug levels. pregnancy-related hypertension. 2. non-dihydropyridines (Non-DHPs) ○ Combination Drug: BiDil ○ Drugs: diltiazem (Cardizem), (Hydralazine + Isosorbide Dinitrate) is verapamil (Calan) FDA-approved for heart failure in ○ Action: Act on both vascular smooth African American patients. muscle and cardiac cells, affecting ○ Nursing Implications: Monitor for heart rate and contractility along with dizziness, headache, and reflex vasodilation. tachycardia. ○ Uses: Commonly used for 2. minoxidil hypertension, angina, and certain ○ Uses: Severe hypertension arrhythmias due to their u