Pharmacology MRCP Exam Questions and Answers

Doxazosin - ANSWER alpha 1 antagonist Treatment for Hypertension and BPH (avoid post sildenafil) Botulinum toxin - ANSWER blepharospasm hemifacial spasm focal spasticity including cerebral palsy patients, han ...

Doxazosin - ANSWER alpha 1 antagonist Treatment for Hypertension and BPH (avoid post sildenafil) Botulinum toxin - ANSWER blepharospasm hemifacial spasm focal spasticity including cerebral palsy patients, hand and wrist disability associated with stroke spasmodic torticollis severe hyperhidrosis of the axillae achalasia PDE-5 inhibitors contraindications - ANSWER Nicorandil > nitrates Alpha antagonists - ANSWER alpha-1: doxazosin alpha-1a: tamsulosin - acts mainly on urogenital tract alpha-2: yohimbine non-selective: phenoxybenzamine Phenylephrine - ANSWER alpha 1 agonist Clonidine - ANSWER alpha 2 agonist Dobutamine - ANSWER Beta 1 agonist Salbutamol - ANSWER beta 2 agonist Mixed alpha and beta blockers - ANSWER Labetalol Carvedilol OCPs - ANSWER increased risk of breast and cervical cancer protective against ovarian and endometrial cancer phase 1 of pharmacokinetics - ANSWER oxidation, reduction, hydrolysis phase 2 of pharmacokinetics - ANSWER conjugation Zero order kinetics - ANSWER HAPE Heparin Aspirin Phenytoin Ethanol First order kinetics - ANSWER Type of kinetics when a constant percentage of substrate is metabolized per unit time aspirin isosorbide dinitrate glyceryl trinitrate lignocaine propranolol verapamil testosterone hydrocortisone Drugs affected by acetylator status - ANSWER Isoniazid, Dapsone Hydralazine, Sulfasalazine Lithium side effects - ANSWER Acute: Course Tremor Chronic: Fine Tremor Lithium adverse effects - ANSWER hand tremors, wt gain polyuria (Nephrogenic Diabetes Insipidus) GI upset Hypothyroidism Teratogenic: Ebstein's Anomaly ECG: T wave flattening/inversion Ebstein's anomaly - ANSWER Tricuspid regurgitation Lithium monitoring - ANSWER Lithium levels every 6 months Renal Function test every 3 months TSH Lithium toxicity and treatment - ANSWER > 1.5mEq/L Treatment: Sodium Bicarb (increases urine alkalinity)/ Haemodialysis Which drug is most likely to precipitate lithium toxicity? - ANSWER DAMN Diuretics ACE inhibitors, Metronidazole NSAIDs TCA Side Effects - ANSWER Antidepressant that has anti-cholinergic side effects include dry mouth, dilated pupil, blurred vision dysrhythmias, sedation, and orthostatic hypotension Lithium drug level monitoring - ANSWER 12hours after dose TCA Overdose - ANSWER "Tri C's" Convulsions Coma Cardiac + Metabolic Acidosis TCA ECG findings (5) - ANSWER - sinus tachycardia - wide QRS - long QT TCA overdose treatment - ANSWER IV sodium bicarbonate Phenytoin Acute Effects - ANSWER Initial: Vertigo, diplopia, Nystagmus, ataxia Later: confusion and seizures Phenytoin chronic side effects - ANSWER Gingival Hyperplasia Megaloblastic Anemia Peripheral Neuropathy Osteomalacia Lymphadenopathy Dyskinesia Phenytoin Idiosyncratic AE - ANSWER fever rashes hepatits aplastic anemia drug induced SLE Phenytoin teratogenicity - ANSWER fetal hydantoin syndrome cleft palate + heart Sodium valproate Mechanism - ANSWER inhibitor by increasing GABA Activity Sodium valproate side effects - ANSWER ↑ appetite and weight gain • Alopecia: regrowth may be curly (phenytoin → hirsutism while valporate → alopecia) • Ataxia • Tremor • Hepatitis (also with phenytoin) • Pancreatitis Teratogenic organophosphate poisoning - ANSWER SLUDGE (Salivation, Lacrimation, urination, Diarrhoea, GI Symptoms, Emesis) Pupils Constricted Monoamine Oxidase Inhibitors (MAOIs) - ANSWER antidepressant medications that increase the amount of monoamine neurotransmitter in synapses (inhibit the enzyme that breaks down serotonin and noradrenaline) Cheese reaction - ANSWER cheese (and foods like red wine and yeast products) have high content of tyramine that SHOULD NOT be ingested while on MAOIs, high NE concentration leads to sympathetic overload causing severe headaches, nausea, and high BP 5-HT3 receptor antagonists - ANSWER Odansetron, dolansetron, granisetron. 5-HT1D agonist - ANSWER Sumatriptan Migraine Treatment 5-HT2 antagonists - ANSWER Pizotifen - migraine prophylaxis? Triptans contraindicated in - ANSWER IHD or cerebrovascular disease bromocriptine, pramipexole, ropinirole - ANSWER dopamine agonists Dopamine agonist Indications - ANSWER Parkinson's disease prolactinoma/galactorrhoea cyclical breast disease acromegaly BZD precautions - ANSWER prescribe for short time 2-4 weeks BZD antidote - ANSWER Flumazenil (Romazicon) BZD withdrawal - ANSWER Switch patients to equivalent dose of Diazepam Reduce every 2-3 weeks by 2mg Class 1A antiarrhythmics MOA - ANSWER Sodium Channel Blocker Class 1A antiarrhythmics - ANSWER Quinidine Procainamide Disopyramide Amiodarone Class 1B antiarrhythmics - ANSWER Lidocaine, mexiletine, and tocainide; dec. AP duration especially in depolarized/ischemia tissue; best following MI Class 1C antiarrhythmics - ANSWER Flecainide, propafenone; no effect on AP, used in ventricular tachycardias; do not use post-MI due to risk for arrhythmias Class 2 antiarrhythmics - ANSWER Beta Blockers Propranolol, Esmolol Class 3 antiarrhythmics MOA - ANSWER Potassium Channel Blocker Class 3 antiarrhythmics - ANSWER amiodarone, sotalol Amiodarone side effects - ANSWER P eripheral neuropathy P hotosensitivity P ulmonary fibrosis + Liver Fibrosis P igmentation of skin - 'Slate grey' appearance P eripheral conversion of T4 to T3 inhibited (hypothyroid) *Amiodarone*-induced Hypothyroidism - ANSWER due to high iodine content of amiodarone *Amiodarone*-induced Hypothyroidism Mx - ANSWER can continue to take the drug if this is desirable (+/- thyroxine) Wolf-Chaikoff effect - ANSWER high levels of iodine inihibit organification Amiodarone induced thyrotoxicosis - ANSWER Type 1: Goitre, Rx with Carbimazole Type 2: Amiodarone related destructive thyroiditis, Goitre absent, Rx with Steroids Class 4 antiarrhythmics - ANSWER CCB (verapamil, diltiazem) Class 5 antiarrhythmics - ANSWER Adenosine, Digoxin Statins - ANSWER HMG-CoA reductase inhibitors Statin monitoring - ANSWER LFT (transaminase) - baseline -> 3 months -> every 12 months CK - baseline -> immediately after drug administration Discontinue Statins if - ANSWER AST rise and persist to 3 times the upper limit Statin myopathy - ANSWER More common in Simvastatin, Atorvastatin statins taken during day or night? - ANSWER during sleep (PNS) - majority of cholesterol manufactured while you sleep Given the history of myalgia, which lipid-regulating drug should be avoided - ANSWER Fibrates > Nicotinic Acid Nicotinic Acid MOA - ANSWER increases HDL levels Beta Blockers overdose management - ANSWER Atropine + Glucagon Beta Blocker Cardiotoxicity - ANSWER Bradycardia Hypotension Heart failure Syncope Furosemide - ANSWER inhibits Na/K/2Cl cotransporter in thick ascending limb of the loop of Henle thus increasing uirnary excretion of K, Mg, and Ca, and renal blood flow WITHOUT altering GFR Furosemide adverse effects - ANSWER • Hyponatremia • Hypokalemia • Hypocalcaemia • Hypochloraemic alkalosis (Hyper pH) • Ototoxicity • Hyperglycaemia (less common than thiazides) • Gout Bendroflumethiazide - ANSWER Inhibits active sodium absorption at early distal tubule Thiazide diuretics - ANSWER Hydrochlorothiazide (HCTZ) Thiazide diuretics side effects - ANSWER -Hyponatremia -Hypokalemia -Hypercalcemia -Hyperlipidemia -Hyperglycemia -Increased uric acid (gout) -Sexual dysfunction Spironolactone - ANSWER aldosterone antagonist acting on distal convoluted tubule Spironolactone Indications - ANSWER Ascites Nephrotic CCF Conn's spirnolactone side effects - ANSWER Hyperkalemia Gynaecomastia drugs causing gynaecomastia - ANSWER Some Drugs Create Awkward Knockers Spironolactone, Digitalis, Cimetidine, Alcohol, Ketoconazole Adenosine pharmacokinetics - ANSWER Dipyridamole increases effect Aminophylline decreases effect