Drugs Affecting Organ Systems PDF

DRUGS AFFECTING THE DIFFERENT ORGAN SYSTEMS CM. URBANO REPRODUCTIVE SYSTEM ESTROGENS AND ANDROGENS Estrogens and androgens are sex hormones produced by the gonads. Necessary for conception, embryonic maturation, and development of 1° and 2° sex chara...

DRUGS AFFECTING THE DIFFERENT ORGAN SYSTEMS CM. URBANO REPRODUCTIVE SYSTEM ESTROGENS AND ANDROGENS Estrogens and androgens are sex hormones produced by the gonads. Necessary for conception, embryonic maturation, and development of 1° and 2° sex characteristics at puberty. Used therapeutically for contraception, management of menopausal symptoms, and replacement therapy in hormone deficiency. ESTROGENS AND ANDROGENS I. ESTROGENS II. SELECTIVE ESTROGEN RECEPTOR MODULATORS (SERMs) III. PROGESTOGENS IV. ANDROGENS ESTROGENS AND ANDROGENS I. ESTROGENS II. SELECTIVE ESTROGEN RECEPTOR MODULATORS (SERMs) III. PROGESTOGENS IV. ANDROGENS  Tamoxifen – currently used in the treatment of metastatic breast CA, or adjuvant therapy following mastectomy or radiation for breast CA. Bazedoxifene – treatment of menopausal symptoms in women with intact uterus in combination with conjugated estrogens. Clomiphene – treatment of infertility Ospemifene - treatment of dyspareunia related to menopause ESTROGENS AND ANDROGENS I. ESTROGENS II. SELECTIVE ESTROGEN RECEPTOR MODULATORS (SERMs) III. PROGESTOGENS IV. ANDROGENS o Progesterone – the natural progestogen o Produced in response to LH by both females and males. o Synthesized by the adrenal cortex in both sexes. o Major uses: Contraception Hormone replacement therapy Synthetic progestogens (progestins): desogestrel dienogest drospirenone Levonorgestrel norethindrone o Medroxyprogesterone acetate – injectable contraceptive o Other uses: control of dysfunctional uterine bleeding treatment of dysmenorrhea management of endometriosis & infertility o Antiprogestin Mifepristone – a progesterone antagonist. Administration of this drug results in termination of pregnancy due to interference with the progesterone needed to maintain pregnancy. Usually combined with Misoprostol (prostaglandin analog) to induce uterine contractions. ESTROGENS AND ANDROGENS I. ESTROGENS II. SELECTIVE ESTROGEN RECEPTOR MODULATORS (SERMs) III. PROGESTOGENS IV. ANDROGENS o A group of steroids that have masculinizing effects in both males and females o Testosterone – the most important androgen in humans. – Synthesized by: – Leydig cells - testes – thecal cells (small amount) - ovaries – Adrenal glands - both sexes – Hypothalamus  GnRH  anterior pituitary gland  FSH and LH  Leydig cells  TESTOSTERONE o Androgen functions: – Required for normal maturation in male – Sperm production – synthesis of muscle proteins and hemoglobin – Decreased bone resorption o Antiandrogens – counter male hormonal action by interfering with synthesis of androgens or blocking their receptors. – flutamide – bicalutamide – enzalutamide – nilutamide o Act as competitive inhibitors of androgens o Effective oral treatment of prostate cancer RESPIRATORY SYSTEM ANTIHISTAMINES Used to block the release or action of histamine – a chemical mediator of inflammation that increases secretions and constricts the air passageway ANTITUSSIVES Agents utilized to block the cough reflex COPD DRUGS Includes bronchodilators, inhaled steroids, leukotriene receptor blockers and other anti- asthma drugs DECONGESTANTS Utilized to decrease the blood flow to the upper respiratory tract and decrease the excessive production of secretions EXPECTORANTS Used to decrease the viscosity of sputum to effectively increase productive cough to clear airways ANTIHISTAMINES Grouped according to  Also called H1 blockers or H1 “generations” antagonist FIRST GENERATION agents - have greater anticholinergic effect and  Relieve respiratory can cause more sedation and symptoms and to drowsiness treat allergic conditions SECOND GENERATION agents- have fewer anticholinergic effects that is why they cause less sedation FIRST GENERATION SECOND GENERATION 1. chlorphenamine 1. loratadine 2. diphenhydramine 2. fexofenadine 3. meclizine 3. cetirizine ANTI-TUSSIVES The following are anti-tussives:  These agents suppress the cough benzonatate – narcotic anti-tissuve reflex on the butamirate citrate – non-narcotic medulla oblongata to suppress cough of codeine – narcotic many respiratory dextromethorphan – non-narcotic conditions. hydrocodone - narcotic MUCOLYTICS  These are agents The following are mucolytics: that breakdown mucous in order to acetylcysteine help respiratory dornase alpha patients in coughing up thick, tenacious secretions  DRUGS FOR COPD  Bronchodilators (adrenergics  Cromolyn sodium and nedocromil – and xanthines) – used to assist act as anti-inflammatory agents by in opening of narrowed airways suppressing the release of histamine  Steroids – used to decrease from the mast cells inflammation  Expectorants – are used to assist in  Leukotriene modifiers – reduce loosening secretions from the airways inflammation in the lung tissue BRONCHODILATORS The following are bronchodilators:  These are helpful in Xanthines – for symptomatic relief or prevention of BA symptomatic relief and reversal of bronchospasm assoc. with COPD or prevention of bronchial asthma sympathomimetics (beta-antagonist) – mimic the effects of the sympathetic NS (dilation of bronchi and bronchospasm and increased rate & depth of respiration) associated with COPD anticholinergics (muscarinic receptor antagonist) – block parasympathetic nerve reflexes that cause airway constriction, and allow them to open Inhaled steroids – decrease inflammatory response in the airway CARDIOVASCULAR SYSTEM  Cardiovascular drugs are very diverse and can therefore be broadly classified according to their pharmacological action. 1. Angiotensin Converting Enzyme inhibitors (ACE) 2. Angiotensin II receptor Antagonists 3. Adrenergic Neuron Blockers 4. Alpha Blockers 5. Beta Blockers 6. Calcium Channel Blockers 7. Diuretics 8. Nitrates 9. Lipid Regulating Agents 10.Cardiac Glycosides 11.Centrally Acting Agents 12.Anticoagulants 13.Antiplatelets  I. ANGIOTENSIN CONVERTING ENZYME INHIBITORS (ACE inhibitors) ACE inhibitors block the conversion of angiotensin l to angiotensin ll. Angiotensin ll is a vasoconstrictor and promotes release of aldosterone, causing salt and water retention, K+ loss and reduces peripheral resistance. ACE inhibitors thus lower blood pressure by vasodilatation and promote loss of salt and water, thereby, elevate serum K+. CLINICAL USES: – Hypertension – Heart Failure – Myocardial Infarction  II. ANGIOTENSIN II RECEPTOR ANTAGONISTS These drugs compete with angiotensin II for tissue binding sites. Mainly act by selective blockage of angiotensin I thus, reducing the pressure effects of angiotensin II. CLINICAL USES: Treatment of hypertension  III. ADRENERGIC NEURON BLOCKERS These drugs act by selectively inhibiting the transmission in the adrenergic nerve endings. CLINICAL USES: – They have been used in hypertension but are now superseded by other antihypertensives – Open-angle glaucoma treatment due to hypertension.  IV. ALPHA ADRENERGIC BLOCKERS / ALPHA ADRENERGIC RECEPTOR ANTAGONISTS These drugs block the effect of alpha1. Blockage of alpha1 adrenoreceptors inhibits vasoconstriction caused by the endogenous catecholamines This causes both arteriolar and venous vasodilation resulting in a fall in blood pressure due to decrease peripheral resistance. CLINICAL USES: – Hypertension – urinary obstruction in Benign prostatic hyperplasia. – Open-angle glaucoma treatment due to hypertension.  V. BETA ADRENERGIC BLOCKERS These drugs are competitive antagonists at beta-adrenergic receptor sites. They reduce cardiac contractibility, thereby reducing arterial pressure pulses. Beta Blockers also block sympathetic stimulation at the sinus node, which decreases the heart rate and cardiac output, thereby lowering the blood pressure. CLINICAL USES: – Treatment of Hypertension & is often combined with diuretics or other antihypertensives. – Angina pectoris, Cardiac arrhythmias, myocardial infarction, Heart Failure. – Control of sympathetic over-activity in alcohol withdrawal, anxiety states, hyperthyroidism, etc. – As eye drop in raised intra-ocular pressure of Glaucoma & ocular hypertension.  VI. CALCIUM CHANNEL BLOCKERS / CALCIUM ANTAGONISTS These drugs inhibit cellular influx of calcium, which is responsible for maintenance of the plateau phase of the action potentials. Calcium Channel Blockers dilate coronary, peripheral arteries and arterioles with little effect on venous tone CLINICAL USES: – Treatment & control of hypertension, angina pectoris & cardiac arrhythmias.  VII. DIURETICS They lower B/P by depleting the volume of sodium and blood volume. Some have vasodilator effects. Others can block the transport function of the renal tubules and prevent water reabsorption. There are several types of diuretics: -Loop Diuretics -Thiazides Diuretics -Carbonic Anhydrase inhibitors Diuretics -Potassium Sparing Diuretics -Others : osmotic diuretics : Anti-diuretic hormone antagonists.  VII. DIURETICS A. Loop Diuretics These products selectively inhibit the reabsorption of sodium in the Loop of Henle, increasing the amount of fluid eliminated by the kidneys. They are the most powerful and efficacious diuretics. They are usually employed in hypertensive crises. CLINICAL USES: – Pulmonary edema with congestive heart failure – Edema that does not respond to less powerful diuretics and is caused by hepatic, renal or cardiac conditions – Hypertension that cannot be controlled with other types of diuretics  VII. DIURETICS B. Thiazides Diuretics They products block the transport function of renal tubules and also inhibit water re- absorption They are well absorbed when given orally and are excreted through the kidneys via urine. CLINICAL USES: – Mild to moderate edema – treatment of essential Hypertension – Fluid retention due to heart failure – hepatic or renal disease  VII. DIURETICS C. Potassium Sparing Diuretics These products inhibits the elimination of potassium from the renal tubules. CLINICAL USE: – Treat hypertension and edema Fluid retention due to heart failure – Prevent hypokalemia  VII. DIURETICS D. Osmotic Diuretics Inhibit reabsorption of water and sodium. Maintain urine output and prevent renal failure as in hypovolemic shock. They reduce intracranial pressure caused by cerebral edema. Reduces intraocular pressure by drawing fluid from the eyes. Eliminates toxins through the kidneys. CLINICAL USE: – Acute renal failure during prolonged surgery or trauma to prevent increased ICP – Glaucoma  VII. DIURETICS E. Carbonic Anhydrate Inhibitors Diuretics These are weak diuretics and are used mainly to reduce raised intra-ocular pressure. CLINICAL USES: – open-angle glaucoma – Epilepsy  VIII. NITRATES These drugs are peripheral and coronary vasodilators. They relax smooth muscles in the blood vessel walls, and thus, help reduce pain of anginal attacks. They redistribute blood flow to ischemic areas of the myocardium, which improves perfusion of the heart. They dilate the veins, reducing venous pressure and venous return. They dilate arterioles, which lowers peripheral vascular resistance. CLINICAL USES: – Acute, Stable & unstable angina, acute & chronic heart failure  IX. LIPID REGULATING AGENTS These drugs are used to modify blood lipid concentration in the management of hyperlipidemia. They are also used in the reduction of cardiovascular arrest. These drugs are grouped into five: A. The Statins - reduce LDL and some triglyceride B. The Fibrates - serum TG and LDL and HDL level C. Bile-acid binding resins - cholesterol by combining with acids in the GIT and prevent their reabsorption D. Nicotinates - TG levels and LDL cholesterol E. Omega-3 Triglycerides - reduce TG in clients with hypertriglyceridemia with risk of ischemic heart disease  X. CARDIAC GLYCOSIDES These products increase cardiac output especially when the heart is failing. They are used to slow the heart rate in supraventricular arrhythmias in heart failure. ADVERSE REACTIONS: - nausea & vomiting, fatigue, drowsiness, confusion, arrhythmias, gynaecomastia Example: – digoxin (Lanoxin) 62.5cmg, 125mcg, 250mcg  XI. CENTRALLY ACTING AGENTS They act by stimulating alpha2 adrenoreceptors in the CNS causing a reduction in sympathetic tone and a resultant fall in blood pressure. They also reduce the heart rate. However, they have been superceeded by other antihypertensive drugs because of their adverse effects.  XII. ANTICOAGULANTS These products are used in the treatment and prophylaxis of thromboembolic disorders. They can be divided into two types: a. Direct anticoagulants b. Indirect anticoagulants  XIII. ANTI PLATELET AGENTS Platelet aggregation is very important in homeostasis. Antiplatelet drugs reduce platelet aggregation and are used to prevent thromembolic events in patients who have suffered myocardial infarction, ischemic stroke or transient ischemic attack or unstable angina. They are also used for primary prevention of thromboembolic events in patients at risk, GASTROINTESTINAL SYSTEM ANTIEMETICS  Drugs that prevent or control Vomiting/Nausea  5HT3 antagonists are used in management of nausea vomiting associated with chemotherapy.  Antihistamine such as diphenhydramine is used for motion sickness and morning sickness.  Metoclopramide is used for gastric emptying in patient’s receiving tube feeding.  Anticholinergic such as hyoscine, Dicyclomine are useful in travel sickness. EMETICS  Drugs which produce Vomiting  They stimulate the chemoreceptor trigger zone and gastric mucosa to induce vomiting.  Indication: To induce vomiting. To treat poisoning. Treatment of overdose of drug LAXATIVES/PURGATIVES  These drugs are known as purgatives, which includes laxatives and cathartics these drugs are used to overcome the constipation and proper evacuation of bowels  Osmotic laxatives (Magnesium hydroxide) draw water into the intestine to increase the mass of stool, stretching musculature which results in peristalsis.  Stimulant laxatives result in stimulation of intestinal peristalsis.  Lubricant laxatives increase water retention in the stool, prevent water absorption from the stool, and lubricate as well as soften intestinal contents.  Stool softener allow more fluid are fat to penetrate the feces, producing a softer fecal mass.  Indications:  To treat or prevent constipation.  To prepare the bowel for radiologic or endoscopic procedures.  Short term treatment of constipation caused high dose of opioid use.  Osmotic laxatives are used to rapid evacuation of the bowel after ingestion of poison or following anti-helminthic therapy to rid of the body from dead parasites. ANTACIDS  They act by neutralizing Gastric acid in the stomach.  They achieve their effects by neutralizing gastric acid, inhibiting gastric acid secretion or protect gastric mucosa. PROTON PUMP INHIBITORS  These agents are used in patient with peptic ulcers (who have failed to respond H2 blockers)  It acts by inhibiting proton pump which is final common step in gastric acid secretion. It also have antisecretory action. ANTIDIARRHEALS  Drug used to control diarrhea is called antidiarrheal drugs.  Antidiarrheals active opioids receptor in G.I. tract to decrease intestinal motility and to increase the absorption of fluid and sodium in the intestine. HISTAMINES (HISTAMINE RECEPTOR ANTAGONIST/H2 BLOCKERS)  They are also called as H2 antagonists. These agents block the action of histamine, thus it reduce the amount of acid released into the stomach. They also promote ulcer healing.  They inhibit gastric acid secretion by inhibiting the action of histamine and histamine 2 receptors in gastric parietal cells. ENDOCRINE SYSTEM HORMONES  Can be from natural, semi-synthetic or synthetic compounds  Hypothalamic and Pituitary Hormones  Steroid Hormones  Thyroid Hormones and Drugs for Thyroid Disorders  Anti-diabetic Agents Insulin Preparations RENAL SYSTEM DIURETICS  Agent that increases urine volume  Increase renal excretion of salt and water  Used to remove excess ECF form the body  There are several types of diuretics:  -Loop Diuretics  -Thiazides Diuretics  -Carbonic Anhydrase inhibitors Diuretics  -Potassium Sparing Diuretics  -Others : osmotic diuretics : Anti-diuretic hormone antagonists. ANTIDIURETICS  Agents that reduce urine volume, opposing diuresis.  Reduces urine flow by acting on reabsorption of water by the renal tubules. CLINICAL USE: – Primary nocturnal enuresis – Nocturia NERVOUS SYSTEM ANALGESICS, ANTIPYRETICS, ANTI- INFLAMMATORY (NSAIDS)  Analgesics is an agent which relieves pain.  Antipyretics which reduce temperature.  Anti-inflammatory which reduce inflammation. Analgesics are divided into two: 1. Narcotic Analgesics (Opioid Analgesics) Its primary main action on central pain mechanism and has narcosis as side effects. - Elevating pain perception threshold. - Changing the pain reaction. (i.e. even in the presence of pain patient does not bother about pain). - Production or induction of sleep. 2. Non-narcotic Analgesics (Non- Opioid Analgesics) Its primary main action on peripheral pain mechanism and does not have narcosis as side effects. - They are effective for mild to moderate headache and pain of musculoskeletal origin, also they lower body temperature. SEDATIVE-HYPNOTICS  Sedative: A drug that reduces excitement and calm the subject without inducing sleep. It may cause drowsiness.  Hypnotics: A drug that induces or maintains sleep, similar to normal arousable sleep.  Tranquilizer: A drug that relieves tension and anxiety without affecting consciousness and without producing drowsiness or sleep. Both sedation and hypnosis may be considered as different grade of CNS Depression. BARBITURATES  These drugs are derivative of barbituric acid. They are general depressant but now a days they are not preferred as sedative and hypnotics.  Exact mechanism is not known. They somehow depress the cerebral cortical activity. HISTAMINE/ANTIHISTAMINE  Histamine is responsible for symptoms of allergy and anaphylactic shock in some following conditions histamine is released.  Antihistamines are the drugs used in the treatment of allergic disorders and some other conditions. Theses drug blocks the effect of histamine and receptors. CNS STIMULANTS  These drugs increased the excitability of nervous tissue this group includes amphetamine, caffeine, analeptics monamine oxidase inhibitors and tricyclic antidepressants.  They increase neurotransmitter levels in the CNS either by increasing neuronal discharge or by blocking in an inhibitory neurotransmitter. SKELETAL MUSCLE RELAXANTS  Muscle relaxants are the drugs which affects skeletal muscle function and decreases the muscle tone. They may be used to alleviate symptoms such as muscle spasm, hyper-reflexia, and pain.  They work directly by acting on the neuromuscular function or indirectly by acting on the CNS and interfere with calcium release in muscle fiber, interfering with muscle contraction at the neuromuscular function. ANTIDEPRESSANTS  Antidepressants are a type of medication used to treat or prevent depression.  Tricyclic antidepressants increase the amount of serotonin, Nor epinephrine, through reuptake inhibition, thus normalizing the hyposensitive receptor site associated with depression.  SSRI ( Selective serotine reuptake inhibitors) block the reuptake of the serotonin into the presynaptic cells, there by increasing serotine levels at the synapse.  Biogenic amines such as 5- hydroxytrptamine, noradrenaline and dopamine are inactivated by the enzyme monoamine oxidase (MAO) MAOI inhibit enzyme MAO that leads to accumulation of these amines in the brain thus produces antidepressant effects. ANTI-MANIC (LITHIUM)  Mania is the condition which characterized with elevated mood with increased emotional liability, excessive talking, increased psychomotor activity with marked euphoria, when mania occur with depression, this condition is known as manic depressive psychosis.  Lithium is the drug used in the treatment of mania. ANTIPSYCHOTICS  Antipsychotics are drugs that are mainly used for the treatment of major psychosis like schizophrenia or mania caused by sipolar disorder they are also called as major tranquillizers.  They block the neurotransmitter dopamine in the limbic system inhibiting transmition of neural impulse (Antipsychotic action). ANTICONVULSANTS  Drugs that prevents or reduce the severity and frequency of seizures in various type of epilepsy ANTIANXIETY (ANXIOLYTICS)  It is a group of mild CNS depressants which are used to control the symptoms of anxiety. They produce a calming effect in anxiety states. ANESTHETICS  An anesthetic is a drug or agent that produce a complete or partial loss of feeling. There are three types of anesthetics:  General: used to produce loss of consciousness before and during surgery  Regional: Topical anesthetics is a local anesthetic which is used to numb the surface of body part.  Local: agent that affect a restricted or specific area of body. Read and study further about the different drugs affecting the different organ systems. THANK YOU!