Table of Contents Groups of side effectsSide effects to memorise Drugs causing…Electrolyte imbalancesOrgan toxicityOther reactionsHere’s a couple relevant OSCE prescribing stations Groups of side effects Anticholinergic: dilated pupils, blurred vision, dry mouth, flushed skin, urinary retention, constipation Tricyclic antidepressants, antihistamines, hyoscine, atropine, antipsychotics, incontinence medications Antihistaminergic: weight gain, sedation Tricyclic antidepressants, antipsychotics, antihistamines Anti-α-adrenergic: postural hypotension, sexual dysfunction, nasal congestion, headache Tricyclic antidepressants, antipsychotics, α-blockers Antidopaminergic: extrapyramidal side effects (e.g. tardive dyskinesias, parkinsonism), hyperprolactinaemia (→ galactorrhoea, oligomenorrhea, subfertility), neuroleptic malignant syndrome, oculogyric crisis Metoclopramide, antipsychotics Side effects to memorise TB drugs Rifampicin: orange-red tears/urine + hepatitis Isoniazid: neuropathy + hepatitis Pyrazinamide: + hepatitis Ethambutol: optic neuritis Antiepileptics Phenytoin: toxicity (→ cerebellar syndrome), acne, coarse face, gum hypertrophy, hirsutism + inhibit COCP Carbamazepine: rash, dizziness, hyponatraemia, hair thinning + inhibit COCP Sodium valproate: tremor, weight gain, hair thinning + teratogenic (avoid if child-bearing age) Lamotrigine: rash (Stevens-Johnson syndrome) Antidepressants SSRI (e.g. fluoxetine, citalopram, sertraline): nausea, low libido, withdrawal, insomnia, hyponatraemia Tricyclic antidepressant (e.g. amitriptyline): [anticholinergic effects], [antihistaminergic effects], [anti-α-adrenergic effects], hyponatraemia (SIADH), arrhythmias Monoamine oxidase A inhibitors (e.g. selegiline): 3Hs – Hypertension, Hepatocellular jaundice, Hyperthermia Antihypertensives ACE inhibitors: dry cough, postural hypotension, acute kidney injury in renal artery stenosis (check U&Es before and 2 weeks after starting), angioedema of the tongue, hyperkalaemia, profound hypotension when started Ca2+ blocker: pedal oedema, headache/flushing/dizziness β-blocker: diabetes risk, impotence, bradycardia, fatigue, cold hands and feet, sleep disturbance α-blocker: [anti-α-adrenergic effects] Diuretics ALL: dehydration, hypotension, hyperuricaemia, hypokalaemia (except K+ sparing), hyponatraemia, hypomagnesaemia Loop: hypocalcaemia (used in treatment of hypercalcaemia) Thiazide (e.g. indapamide): hypercalcaemia K+ sparing: hyperkalaemia, gynaecomastia DMARDs Sulfasalazine: myelosuppression, oligospermia, hepatitis, rashes (Stevens-Johnson syndrome, erythema nodosum), renal problems, discoloured urine Chloroquine: retinopathy, tinnitus, myopathy Methotrexate: hepatic toxicity, pulmonary toxicity, myelosuppression, mucositis TNF antagonists: infusion reactions (including anaphylaxis), infections (including TB reactivation), autoimmune reactions, blood disorders Cyclophosphamide: haemorrhagic cystitis, myelosuppression, alopecia Hypoglycaemics Insulin: hypoglycaemia, fat-hypertrophy at injection site, hypokalaemia (used in treatment of hyperkalaemia), weight gain Metformin: weight loss, lactic acidosis, metallic taste, GI disturbance, B12 deficiency Sulphonylureas (e.g. gliclazide): hypoglycaemia, weight gain Thiazolidinediones (glitazones, e.g. pioglitazone): fluid retention (→ heart failure, oedema), hepatotoxicity, fractures DPP4-inhibitors (gliptins, e.g. sitagliptin): pancreatitis SGLT2-inhibitors (flozins, e.g. empagliflozin): UTIs/thrush, risk of DKA, weight loss, may increase risk of amputations Contraception See here. Antipsychotics ALL: [antidopaminergic effects], [anticholinergic effects], [antihistaminergic effects], [anti-α-adrenergic effects] Clozapine: agranulocytosis Chlorpromazine: cholestatic jaundice Haloperidol: prolonged QT interval, interference with temperature regulation Antiarrhythmics Amiodarone: thyroiditis, pulmonary fibrosis, peripheral neuropathy, myopathy, blue-grey skin pigmentation/photosensitivity, hepatitis, metallic taste Digoxin toxicity: xanthopsia (yellow/orange tinge to vision), GI distress, any arrhythmia Adenosine: flushing, sense of impending doom Others Lithium: toxicity (tremor/ataxia/dysarthria → coma, convulsions, hypotension), diarrhoea, hypothyroidism, diabetes insipidus Steroids: diabetes risk, cushingoid appearance, psychosis, osteoporosis, hypokalaemia, hyperglycaemia, infections, leukocytosis, risk of avascular necrosis Azathioprine: myelosuppression Ciclosporin: tremor, chronic interstitial nephritis, hypertrichosis, gum hyperplasia, burning sensation in hands/feet Levodopa: nausea, red urine/other body fluids, postural hypotension, dyskinesias, ‘on-off’ and ‘wearing off’ effects Proton pump inhibitor: tinnitus, GI disturbance, headache, hyponatraemia, hypomagnesaemia Drugs causing… Electrolyte imbalances Hypernatraemia: sodium-containing antibiotics/fluids, sodium bicarbonate, drugs causing diabetes insipidus (e.g. lithium) Hyponatraemia: antidepressants, diuretics, chlorpromazine, carbamazepine, proton pump inhibitors, ACE inhibitors Hyperkalaemia: K+ sparing diuretics, ACE inhibitors/angiotensin receptor blockers, NSAIDs, trimethoprim, ciclosporin/tacrolimus, heparin Hypokalaemia: salbutamol (used in Tx of hyperkalaemia), insulin, diuretics (except K+ sparing), caffeine/theophylline Hypercalcaemia: thiazide diuretics, lithium Hypocalcaemia: loop diuretics, bisphosphonates, phenytoin Organ toxicity Hepatitis: TB antibiotics (rifampicin/isoniazid/pyrazinamide), sodium valproate, methotrexate, methyldopa, amiodarone, statins, paracetamol, phenytoin, ketoconazole/fluconazole, nitrofurantoin, sulfonylureas/sulfonamides Cholestasis: co-amoxiclav (may be delayed/severe), clarithromycin/erythromycin, carbamazepine, chlorpromazine, contraceptives, flucloxacillin, sulfonylureas/sulfonamides Pulmonary toxicity/fibrosis: nitrofurantoin, amiodarone, methotrexate, cyclophosphamide, sulfasalazine, bleomycin Renal impairment Interstitial nephritis: NSAIDS, penicillins/cephalosporins, calcineurin inhibitors (ciclosporin/tacrolimus), PPIs Acute tubular necrosis: lithium, contrast, gentamicin, amphotericin B Precipitate renal artery stenosis: ACE inhibitors Glomerular damage: NSAIDs Creatinine rise: trimethoprim, cimetidine/ranitidine Photosensitivity: tetracyclines, terbinafine, chlorpromazine, amiodarone (→ blue/grey discoloration), chemo (vincristine), ciprofloxacin, psoralens, retinoids, thiazide diuretics, sulphonylureas Hypothyroidism: amiodarone, carbimazole, lithium, propylthiouracil, radio-iodine Other reactions Stevens-Johnson syndrome/erythroderma: sulphur-based drugs (sulphonamides, sulfonylureas), antiepileptics, allopurinol, antibiotics Vasculitis: allopurinol, penicillin, sulphonamides, thiazides, phenytoin, cephalosporins Agranulocytosis: C’s – Carbamazepine, Clozapine, Colchicine, Carbimazole, Cytotoxic agents Gynaecomastia: DISCO MTV – Digoxin, Isoniazid, Spironolactone, Cimetidine, Oestrogens, Methyldopa/metronidazole, Tricyclic antidepressants, Verapamil Neuropathy: metronidazole, nitrofurantoin, isoniazid, vincristine, cisplatin, amiodarone, phenytoin Megaloblastic anaemia: methotrexate, phenytoin, ethanol, trimethoprim, sulfonamides, sodium valproate, metformin, antidepressants Dyskinesia: dopaminergic drugs (levodopa, bromocriptine), dopamine-blocking drugs (antipsychotics), antidepressants Clostridium difficile risk: cephalosporins, clindamycin, ciprofloxacin, broad spectrum penicillins Here’s a couple relevant OSCE prescribing stations Medication review Antidepressant counselling Find more here!
