Pharmacology for Hypertension Management

NUR2047 Pharmacology - Cardiovascular and Hematopoietic System

• This course covers medications for the cardiovascular and hematopoietic systems.

Medications for Cardiovascular System

• Anti-hypertension drugs: Include beta-blockers, calcium channel blockers, ACE inhibitors, ARB blockers, centrally acting antihypertensive drugs, and vasodilators.

• Antianginal drugs: Include nitrates (short-acting and long-acting), beta-blockers, and calcium channel blockers.

• Drugs for Cardiovascular Diseases: Cover antidysrhythmics and inotropes.

• Lipid-lowering drugs: Cover statins, bile-sequestering drugs, fibrates, and nicotinic acid.

• Anticoagulants: Include heparin (unfractionated and low molecular weight), vitamin K antagonists (e.g., warfarin), direct thrombin inhibitors (DTIs), and direct factor Xa inhibitors.

• Antiplatelets: Include COX-1 inhibitors (e.g., aspirin), P2Y12 receptor antagonists (e.g., clopidogrel, prasugrel, ticagrelor), and phosphodiesterase inhibitors (e.g., dipyridamole).

• Thrombolytics: Tissue plasminogen activator (tPA).

Hypertension

• Hypertension is the pressure exerted on blood vessels during heart contraction and relaxation, measured in mmHg.
• Systolic blood pressure (SBP) is recorded during heart contraction and diastolic blood pressure (DBP) during relaxation.
• Blood pressure categories include optimal, normal, high normal, and hypertension, with corresponding systolic and diastolic ranges.
• There are various recommendations for rechecking blood pressure based on the readings.
• Asymptomatic, mild headache can be a symptom of high blood pressure.
• Dangerous high blood pressure (malignant hypertension) can lead to serious complications like stroke, myocardial infarction, and kidney damage.

A1. Beta-blocker (Examples)

• Selective beta-blockers (B1): Acebutolol, Atenolol, Bisoprolol, Metoprolol, Esmolol, Bisoprolol + hydrochlorothiazide, Labetalol.

• Non-selective beta-blockers (B1, B2): Nadolol, Propranolol, Sotalol, Carvedilol.

• Side effects: tiredness, cold hands and feet, slow heartbeat, diarrhea, nausea,sleep disturbances, nightmares and erectile dysfunction.

• Special nursing alerts: can trigger asthma, mask hypoglycemia in diabetics, may worsen uncontrolled heart failure or hypotension, or certain rhythm problems.

A2. Calcium Channel Blockers (Examples)

• Dihydropyridines: Nifedipine, Amlodipine, Felodipine, Nimodipine, Lercanidipine, Lacidipine

• Non-dihydropyridines: Verapamil, Diltiazem.

• Side effects: flushed face, headaches, dizziness, swollen ankles, hypotension, reflex tachycardia, constipation, and bradycardia.

• Special nursing alerts: Avoid large quantities of grapefruit juice, high-fiber diet, and plenty of fluids to reduce constipation.

A3. Diuretics (Examples)

• Indapamide, Furosemide (Lasix), Spironolactone (Aldactone)

• Side effects: flushed face, headaches, swollen ankles, constipation, dizziness, tiredness.

• Special nursing alerts: Take in the morning, monitor for hypokalemia, educate patients on preventing postural hypotension, and ensure accurate records of daily body weights.

A4. ACE Inhibitors (Examples)

• Captopril, Enalapril, Lisinopril, Perindopril, Ramipril.

• Side effects: persistent dry cough (most common), dizziness, taste disturbance, and rashes.

• Special nursing alerts: Not suitable during pregnancy, avoid salt substitutes or potassium supplements, and should typically be taken before meals (unless otherwise specified).

A5. Angiotensin II Receptor Blockers (ARBs, Examples)

• Candesartan, Irbesartan, Losartan, Telmisartan, Valsartan.

• Side effects: Headache, dizziness.

• Special nursing alerts: Not suitable during pregnancy, medications may raise potassium levels in the blood, and ARBs are less likely to have side effects than ACE inhibitors.

A6. Centrally Acting Antihypertensive Drugs (Example)

• Methyldopa (Aldomet)

• Side effects: Headache, postural hypotension.

• Special nursing alerts: Should not drive or operate machinery (due to dizziness), avoid alcohol, may rarely cause fatal liver disease or anemia, and may be used to manage hypertension in pregnancy.

A7. Vasodilators (Example)

• Hydralazine (Apresoline)

• Side effects: angina, swelling in arms and legs, flushing, gastrointestinal disorders, headache, joint disorders, muscle pain, nasal congestion, and palpitations.

• Special nursing alerts: Inform your doctor of any symptoms like arthritis, fever, or tiredness.

Anti-hypertensive Drugs - General Advice

• Combination with lifestyle modification (diet + exercise + quit smoking + less alcohol) is important for better and lifelong management.
• Medications often start at low doses, and a second from a different class can be added if needed.
• Proper education for patients is crucial, including taking drugs regularly, checking for drug compliance, not driving or operating machinery while on medication, and reporting pregnancy to the doctor.
• Patients should track their blood pressure and discuss self-monitoring strategies with their doctor.

B. Antianginal Drugs

• Nitrates: short-acting and long-acting
• Beta-blockers
• Calcium channel blockers

Angina

• Stable angina: regular pattern, triggered by exertion, relieved by rest and medication
• Unstable angina: unpredictable, frequent attacks, even at rest, could indicate a heart attack
• Variant angina: occurs at rest, often requires medication intervention

Drugs Management Plan (for Angina)

• Initial treatment could be beta-blockers, calcium channel blockers or both. An additional, short-acting nitrate is often appropriate to relieve angina attacks.

• Short-acting nitrates: for immediate relief. (Examples - nitrostat, Nitro-bid, Imdur.)

• Long-acting nitrates: designed for long-term prevention of symptoms. (Examples - Isordil, Elantan.)

• Alternative antianginal drugs are available if initial drugs are not tolerated.

B1. Nitrates

• Nitrates work by converting to nitric oxide, resulting in peripheral vasodilation, decreasing preload, afterload and workload. Coronary vasodilation increased blood supply to the myocardium.

Routes for Nitroglycerin (NTG) Medications

• Sublingual tablets
• Sublingual spray
• Transdermal patches
• Slow IV infusion.

Patient Instructions - What to Do When Feeling Angina

• Assess for symptoms
• Stop activity
• Take medications as directed
• Follow-up with medical professional if pain persists

Nitrate Side Effects / Contraindications

• Side effects: Hypotension (low blood pressure), throbbing headache, warmth/flushed face.
• Contraindications: Avoid concomitant use with alcohol or medications for erectile dysfunction (may induce severe hypotension.)

Nitrate More Special Nursing Alerts

• Avoid machinery/high-alert tasks
• Caution with severe hepatic or renal impairment
• Drug interactions with other cardiovascular medications
• proper storage and use time for medications

How to Apply Glyceryl Trinitrate (NTG) - Transdermal Patch?

• Clean the area with no hair, scars, cuts.
• Follow application guidelines
• Don't expose to direct heat
• Avoid applying to the same location within 14 days.

How to Use NTG Sublingual (SL) Spray?

• Follow steps and guidelines
• Hold the spray under the tongue, don't swallow/inhale
• Store the medication at a suitable temperature.

Antianginal Drug List

• Provides a list of long-acting nitrates, beta-blockers, and calcium channel blockers

C. Drugs for Cardiovascular Diseases

• Anti-dysrhythmics: Digoxin, Amiodarone, Diltiazem
• Inotropes: Dopamine

C1. Anti-dysrhythmics - Digoxin

• Side effects: Cardiac symptoms (bradycardia, heart block, palpitations), neurologic symptoms (headache, dizziness, confusion, hallucinations), GI symptoms (nausea, vomiting, diarrhea), visual disturbances (blurred or yellowish vision, seeing halos).
• Special nursing alerts: Monitor for any slow heart rate, low blood pressure, blurred vision, and renal function tests (especially potassium). Report electrolyte deficits or low potassium levels.

C1. Anti-dysrhythmics - Amiodarone

• Side effects: Nausea, vomiting, taste disturbances, raised serum transaminases, jaundice, bradycardia, pulmonary toxicity, tremor, headache, sleep disorders, hypothyroidism, hyperthyroidism, and skin discoloration.
• Special nursing alerts: Monitor thyroid, liver, and pulmonary function regularly. Correct electrolyte disorders before starting treatment. Chest x-ray is recommended..

C1. Anti-dysrhythmics - Diltiazem

• Side effects: Headache, fatigue, dysrhythmia, heart block (asystole), bradycardia, heart failure, nausea, vomiting, diarrhea, dizziness, flushing, light-headedness.
• Special nursing alerts: Monitor BP, pulse, ECG (PR, QRS, QT intervals). Notify doctor if SBP < 90 mmHg or HR < 50 bpm. Swallow tablets whole; avoid grapefruit juice/avoid interference with other drugs or substances.

C2. Intropin - Dopamine

• Side effects: Nausea, vomiting, orthostatic hypotension, headache, dizziness, cardiac arrhythmia.
• Indications: Cardiogenic and septic shock, hypotension.

D. Lipid Lowering Drugs

• Statins: (e.g., atorvastatin, fluvastatin, lovastatin, rosuvastatin, pravastatin, simvastatin)
• Bile-sequestering drugs: (e.g., cholestyramine)
• Fibrates: (e.g., bezafibrate, fenofibrate, gemfibrozil)
• Nicotinic acid: (e.g., niacin)

D1. Statins (Examples)

• Side effects: Gastrointestinal discomfort, muscle pain, and abnormal liver function (abnormal liver function tests).
• Special nursing alerts: Monitor for unexplained muscle pain, weakness or dark urine; yellowing of skin/eyes; severe gastrointestinal problems (appetite loss); Monitor liver function tests (LFTs); Avoid grapefruit juice; Not suitable for pregnancy.

D2. Bile acid sequestering (BAS) Drugs

• Side effects: Gastrointestinal discomfort, constipation, nausea, and may increase triglycerides.
• Special nursing alerts: Do not take in dry powder form; should be mixed with liquid; High-fiber diet and plenty of fluids to reduce side effects; Other medications should be taken at least 1 hour before or 4-6 hours after; Alert for pregnancy.

D3. Fibrates

• Side effects: Gastrointestinal discomfort (nausea, anorexia), rash, vertigo, headache.
• Special nursing alerts: May increase the effect of other blood thinners (like warfarin); May interact with some statins. Alert for patients with renal or thyroid disease.

D4. Nicotinic Acid

• Side effects: Warmth or redness in the face or neck, hyperglycemia, gout, hepatotoxicity, mild nausea, or vomiting, diarrhea.
• Special nursing alerts: High doses may cause liver damage; Monitor LFTs; Avoid use during pregnancy or breastfeeding; Take with a low-fat meal, avoid alcohol, and spicy foods.

E. Anticoagulants

• Parenteral anticoagulants: Heparin (unfractionated and low-molecular-weight).
• Oral anticoagulants: Vitamin K antagonists (e.g., warfarin), direct thrombin inhibitors (DTIs), and direct factor Xa inhibitors.

E1. Heparins

• Actions: Activates antithrombin III, which inhibits thrombin and factor Xa in the blood clotting cascade.
• Indications: Treatment of acute and chronic coagulopathies, disseminated intravascular coagulation, blood transfusions, extracorporeal circulation, and dialysis procedures.
• Special Nursing Alerts: Monitoring for potential side effects, especially bleeding, noting potential patient education on possible side effects
• Low-molecular-weight heparins: generally require less frequent monitoring compared to unfractionated heparin.

E2. Vitamin K Antagonists - Warfarin

• Actions: Inhibits vitamin K, thus decreasing the production of clotting factors. (Factors II, VII, IX, and X.)
• Special Nursing Alert: Important to monitor (International normalized ratio, INR), and not given during pregnancy; may interact with other medications; dietary changes must be considered to mitigate potential effects of the drug.
• Dosage regimen: Varies based on patient's condition/response, but often administered on a scheduled basis.

E3. Direct Thrombin Inhibitors (DTIs)

• Actions: Directly inhibits thrombin.
• Side effects: Bleeding
• Special Nursing Alerts: Caution in elderly and patients with low body weight; caution with patients with bleeding disorders, thrombocytopenia; concomitant use of drugs.

E4. Direct Factor Xa Inhibitors

• Actions: Inhibits factor Xa.
• Side effects: Bleeding
• Special Nursing Alerts: Caution in patients at risk of bleeding; avoid concomitant use with drugs.

F. Antiplatelets

• COX-1 inhibitors (aspirin); P2Y12 receptor antagonists (clopidogrel, ticagrelor, prasugrel); Phosphodiesterase inhibitors (dipyridamole).

F1. COX-1 inhibitor - Aspirin

• Mechanism of action: Inhibits platelet cyclooxygenase (COX) which is critical for platelet activation and aggregation.
• All registered antiplatelet drugs: are prescription-only, except aspirin.
• Side Effects and Special Nursing Alerts: Monitor for gastrointestinal irritation, haemorrhage and increased risk of bleeding in renal impaired or patients with asthma and previous peptic ulceration. Avoid use in patients with increased risk of bleeding, or where it is contraindicated.

F2. P2Y12 Receptor Antagonists

• Mechanism of Action: Prevent blood aggregation by inhibiting ADP receptor.
• Examples: ticlopidine, clopidogrel, prasugrel, and ticagrelor.
• Side Effects and Nursing Alerts: Monitor for hemorrhages, gastrointestinal disturbances, rash, blood dyscrasia, and bleeding in patients with risk factors.

F3. Phosphodiesterase Inhibitors

• Mechanism of action: Inhibits adenosine uptake and cyclic GMP phosphodiesterase activity, which decreases platelet aggregability.
• Examples: Dipyramidole
• Side Effects and Special Nursing Alerts: Increased risk of blood bleeding, angina worsening, aortic stenosis, recent myocardial infarction, use with caution in pregnancy/lactation, impaired renal/liver function/bleeding disorders.

G. Thrombolytics

• Tissue plasminogen activator (tPA): Dissolves blood clots (thrombi) in blood vessels.

G1. Tissue Plasminogen Activator (tPA)

• Mechanism of Action: Activating plasminogen into plasmin, which then breaks down fibrin strands in blood clots.
• Indications: Acute myocardial infarction, acute ischemic stroke, peripheral artery occlusion, and thrombi in arterial-venous cannulas.
• Special Nursing Alerts : Ensure an adequate assessment and monitoring.

H. Drugs for Hematopoietic Disorders

• G1. Tranexamic Acid (Transamin): An antifibrinolytic agent that prevents the breakdown of blood clots.
• G2. Iron/Drugs for Anemia: Iron salts, vitamin supplements (e.g. vitamin B9, B12, Folic acid) to treat anemia, where the body is deficient in iron or other nutrients.

G2. Iron/ Drugs for Anemia

• Special Nursing Alerts: Oral iron is taken best when on an empty stomach; avoid taking with substances that reduce absorption (tea/coffee, antacids, milk); monitor for any dark/colored stools; educate patients on side effects.

General Advice/Additional Information

• Other factors are important in managing cardiovascular and blood related diseases. This includes lifestyle changes (diet/exercise/weight management), monitoring/tracking of current conditions, and consulting with appropriate healthcare professionals (doctor/pharmacist.)

Test your knowledge on pharmacological treatments for hypertension, including mechanisms of action, common medications, and nursing considerations. This quiz covers various drug classes such as beta-blockers, diuretics, and ARBs. Assess your understanding of both medication effects and lifestyle modifications in managing high blood pressure.