# Antihypertensive Drug Selection > Antihypertensive drug selection — compelling indications, pregnancy, resistant hypertension, emergencies — decision-ready MBBS Pharmacology notes. - Canonical URL: https://prepelephant.com/topics/mbbs/pharmacology/antihypertensive-drug-selection - Exam / course: MBBS · Subject: Pharmacology - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-02 - Last updated: 2026-10-02 - How to cite: "Antihypertensive Drug Selection", PrepElephant, https://prepelephant.com/topics/mbbs/pharmacology/antihypertensive-drug-selection ## Direct answer Antihypertensive selection is not one decision but a match between patient and compelling indication: thiazides, calcium channel blockers, ACE inhibitors and ARBs are the first-line four for uncomplicated hypertension, while comorbidity redirects the choice — ACE inhibitor or ARB for proteinuric diabetes, beta-blocker plus ACE inhibitor after infarction, spironolactone add-on for resistant hypertension, and labetalol, methyldopa or nifedipine in pregnancy. Hypertensive emergencies demand intravenous therapy (labetalol, nitroprusside, nicardipine) with controlled reduction over 24–48 hours, whereas urgency is managed orally. ## What you must remember - First-line classes for most patients: thiazide-type diuretic, calcium channel blocker, ACE inhibitor, ARB — start one, titrate to target (below 140/90 generally, below 130/80 in many high-risk groups per current guidance). - Compelling indications framework: diabetes with proteinuria — ACE inhibitor/ARB; post-myocardial infarction — beta-blocker plus ACE inhibitor; heart failure — ACE inhibitor/ARB, beta-blocker, mineralocorticoid antagonist, diuretic; chronic kidney disease with proteinuria — ACE inhibitor/ARB. - Pregnancy: labetalol, methyldopa, nifedipine, hydralazine; ACE inhibitors and ARBs are contraindicated throughout. - Beta-blockers are no longer first-line for uncomplicated hypertension but remain mandatory with angina, heart failure, post-infarction and rate control. - Avoid: thiazides in gout; beta-blockers in asthma and peripheral vascular disease with rest pain; non-dihydropyridines in systolic heart failure; ACE inhibitors in bilateral renal artery stenosis and pregnancy. - Resistant hypertension (uncontrolled on three drugs including a diuretic at optimal dose): add spironolactone 25 mg — the proven fourth drug. - Hypertensive emergency (pressure above 180/120 with acute target-organ damage): labetalol, nicardipine, nitroprusside, or enalaprilat intravenously, lowering mean pressure by no more than 20–25 per cent in the first hours. - Pheochromocytoma: alpha-blockade before beta; clonidine withdrawal and non-steroidal drugs are classic secondary or resistant causes. ## How to work through five different patients The drug class is chosen by the comorbidity, and five outpatient vignettes cover the map. A 48-year-old diabetic with 2+ proteinuria gets an ACE inhibitor even at modest pressures — renoprotection is the indication, and ARB if he coughs. A 60-year-old two months after an anterior infarction, already on aspirin and statin, gets a beta-blocker plus an ACE inhibitor for prognosis, not merely for pressure. A 70-year-old with isolated systolic hypertension and constipation gets amlodipine or indapamide — a thiazide's stroke data suits the elderly, and indapamide spares his glucose. A 26-year-old woman at 32 weeks of pregnancy at 160/105 gets labetalol orally (or methyldopa), and if she seizes, magnesium sulphate is the anticonvulsant while hydralazine or labetalol intravenously controls pressure. Finally, a 55-year-old on three maximised drugs returns at 150/94 with normal electrolytes: confirm adherence, exclude non-steroidal use and sleep apnoea, screen for secondary causes, then add spironolactone. Each vignette is a row in the compelling-indications table that Indian postgraduate examinations recycle every year. ## Where students slip The penalised answers are predictable. Writing an ACE inhibitor for a pregnant hypertensive is the single most punished error in the chapter. Second, reaching for sublingual nifedipine in hypertensive emergency — an uncontrolled precipitous fall in pressure can cause stroke or infarction; the exam wants controlled intravenous reduction or oral therapy over 24–48 hours. Third, forgetting that in a patient of African ancestry or the elderly with low-renin hypertension, calcium channel blockers and thiazides outperform renin-angiotensin monotherapy — a pharmacodynamic point about renin status rather than an epidemiological one. Fourth, missing secondary-cause clues: young age, sudden onset, abdominal bruit, hypokalaemia without diuretics (Conn syndrome), and paroxysmal sweating-palpitation-headache triads (phaechromocytoma) each redirect the work-up before any drug is chosen. ## Frequently asked questions ### Which four classes are first-line for uncomplicated hypertension? Thiazide-type diuretics, calcium channel blockers, ACE inhibitors and ARBs, chosen by comorbidity, cost and tolerability, titrated to target and combined rationally rather than maximised sequentially. ### How is hypertension managed in pregnancy? Labetalol, methyldopa, extended-release nifedipine or hydralazine, with magnesium sulphate for eclamptic seizures; ACE inhibitors and ARBs are absolutely contraindicated at every stage. ### What defines resistant hypertension and its next step? Blood pressure above goal on three drugs including a diuretic at optimal doses; after excluding non-adherence, NSAIDs and secondary causes, add spironolactone 25 mg — the best-evidenced fourth drug. ### Why is sublingual nifedipine condemned in hypertensive emergencies? It produces abrupt unpredictable falls in pressure, risking cerebral and myocardial ischaemia; controlled intravenous reduction of mean arterial pressure by 20–25 per cent in the first hours is the standard. ### Which antihypertensive suits a patient with coexisting benign prostatic hyperplasia? An alpha-1 blocker such as doxazosin can be added for both indications, though it is add-on therapy rather than first-line for pressure alone.