Flashcards in Pharmacology Deck (156)
Cardiac glycoside used to slow HR in atrial fibrillation (-ve chronotrope, +ve inotrope) and for heart failure in patients still symptomatic following diuretics and ACE-Is. Narrow therapeutic index.
Directly acting adrenoceptor agonist - beta 1 selective. Stimulates cardiac contraction without major effect on HR (+ve inotrope). Treats heart block, half-life 2mins (rapid metabolism by COMT), lacks isoprenaline's reflex tachycardia.
Beta-1 selective beta-blocker used to treat angina, post MI, dysrhythmias, CHF, hypertension. Not safe for asthmatic patients.
Diltiazem + verapamil
Rate limiting/slowing Ca channel blockers (cardiac and smooth muscle actions). -ve inotropic effect Verapamil > Diltiazem. Ca be used to control/correct dysrhythmias. Verapamil is a Phenylalkaylamine, Diltiazem is a Benzothiazepine. Can double Carbamezepine levels (anti-convulsant/mood stabiliser).
Enalapril + captopril
ACEI - reduces preload and afterload. Used for hypertension, HF, post-MI, diabetic nephropathy, progressive renal insufficiency, high CVD risk.
Angiotensin II receptor blocker (ARB/AIIA). Antagonist of AT1 receptors. Hypertension as alternative to ACEIs with less side effects, CHF in patients who cannot tolerate ACEIs.
K channel opener and Organic nitrate that stimulates guanylate cyclase to cause vasodilation. Used for angina, acute and chronic HF, BP control during anaesthesia. Adverse effects - hypotension and headache.
aka bendroflumethiazide. Thiazide diuretic. Inhibit Na and Cl reabsorption in early distal tubule. Increases Na/Cl, K and Mg loss, Ca reabsorption. Moderate increase in urine volume. Used for HF, hypertension, severe resistant oedema, idiopathic hypercalciuria, nephrogenic diabetes insipidus. Side effect - inhibits insulin secretion (DM)
Potassium sparing diuretic/aldosterone receptor antagonist. Acts in the distal convoluted tubule. Small increase in urine volume and Na loss. Used for primary and secondary hyperaldosteronism. Side effects - gynaecomastia, menstrual disorders, hyperkalaemia.
Wide spectrum anti-arrhythmic used for supraventricular and ventricular tachyarrhythmias. Prolongs cardiac action potentials. Adverse effects - accumulation in body (long half life) causes photosensitive skin rashes, hypo-/hyper-thyroidism, pulmonary fibrosis, corneal deposits, Neuro and gastro disturbances. Potent inhibitor of Phenytoin (antiepileptic) metabolism.
Organic nitrate that releases NO into smooth muscle causing vasodilation. Often given sublingually for rapid relief of angina - short half life ~5mins. Via transdermal patch gives longer action. Prolonged use associated with tolerance.
Anti hypertensive vasodilator that also slows/prevents hair loss. Potassium channel opener causing hyperpolarisation.
Competitive Alpha-1 adrenoceptor blocker -> antihypertensive and coronary vasodilator but associated with increased rates of CHF by ALLHAT study. Can induce postural hypotension.
5HT-1D receptor agonist. Constricts large arteries and inhibits trigeminal nerve transmission. Used to treat migraines - contraindicated if have coronary disease.
Thrombolytic - converts plasminogen to plasmin (natural fibrin protease). Bacterial product hence tolerance develops after first admin. Used in the treatment of MI.
Thrombolytic - converts plasminogen to plasmin (natural fibrin protease). Recombinant plasmin activator. Used in the treatment of acute MI and ischaemic stroke. Must be given within 12 hrs symptom onset.
Anticoagulant - Vitamin K antagonist. Long delay of onset (~5days) narrow therapeutic window, unpredictable pharmacokinetics and numerous drug interactions. Protein binding interactions most clinically significant with warfarin. Phenytoin (antiepileptic) increases clearance.
Anticoagulant - activates Antithrombin-III (LMWHs also inhibit factor Xa). Short half life ~1hr, LMWHs longer.
Antiplatelet activator - irreversible non-specific cyclo-oxygenase inhibitor (but binds COX-1 more avidly) - prevents platelet production of thromboxane A2. At higher doses also inhibits endothelial COX preventing production of protective prostacyclin PGI2 (COX-2). Major side effects - gastric irritation + ulceration, bronchospasm in asthmatic (pseudoallergy), prolonged bleeding times, nephrotoxicity. Can displace other drugs from albumin increasing their free conc. Preferentially absorbed in stomach (acid pH) but majority in gut.Analgaesic - inhibiting prostanoid (PG) synthesis prevents sensitisation of nociceptors thus increases threshold for pain.
Antiplatelet activator - ADP/P2Y receptor antagonist.
Antiplatelet activator - Glycoprotein IIb/IIIa receptor antagonist. GPIIb/IIIa receptor plays important role in platelet aggregation. Used for treatment of thrombotic disorders.
HMG-CoA reductase inhibitor. Lipid lowering drug. Used to treat dyslipidemia and to prevent CVD. Grapefruit juice inhibits cytochrome P450 thus inhibits metabolism. Side effects - rhabdomyolysis.
Typical non-selective NSAID. Inhibits COX reversibly. Has anti-inflammatory, analgesic and anti-pyretic actions.
Selective COX-2 inhibitor. Get fewer ulcers than with non-selective NSAIDs. Increased risk to CVS however - MIs
Osmotic diuretic - inert, filtered but not reabsorbed, decreases water reabsorption. Clinically used to prevent acute renal failure, decrease intra-cranial and ocular pressures. Side effects - increases ECF volume, hyponatraemia.
Carbonic anhydrase inhibitor - acts on the proximal tubule to prevent reabsorption of HCO3 and Na. Weak diuretic. Clinical used for renal stones, metabolic alkalosis and to decrease intra-ocular pressure. Unwanted - K loss and met. acidosis
Aka furosemide - Loop diuretic. Blocks the Na/Cl/K transport in the ascending limb of loop of Henle. Decreases the osmolarity of the medullary interstitium hence reduced concentrating power of collecting duct. Leads to a large increase in urine volume, Na, Cl, K, Ca and Mg loss. Clinical uses - oedema, moderate hypertension, hypercalcaemia, hyperkalaemia. Unwanted effects - hypovolaemia, hypotension, metabolic alkalosis (K loss)
Potassium sparing diuretic - aldosterone-sensitive Na channel inhibitor. Prevents Na reabsorption from the early distal tubule - increases Na and uric acid loss but H retention. Small increase in urine volume. Clinical uses - combine with K losing diuretics. Unwanted effects, hyperkalaemia, metabolic acidosis.
Anti-emetic. Competitive antagonist at histaminergic (H1), cholinergic (M), and dopaminergic receptors (D2). Acts centrally (labyrinth, NTS, VC) to block activation of vomiting centre. Used to treat/prevent - motion sickness, labyrinth disorders (Meniere's), hyperemesis gravidarium, pre- and post-operatively. Unwanted effects - dizziness, tinnitus, fatigue, sedation, excitation in excess, convulsions, anti-muscarinic effects.