Antihypertensives
Also known as: blood pressure medications, antihypertensive drugs
Antihypertensives are medications that lower blood pressure to reduce the risk of stroke, heart attack, heart failure, and kidney disease. The major classes include diuretics, ACE inhibitors, angiotensin receptor blockers, calcium channel blockers, and beta blockers.
Antihypertensives treat hypertension by acting on the three determinants of blood pressure: blood volume, vascular resistance, and cardiac output. Because hypertension is usually asymptomatic, these drugs are prescribed to prevent long-term organ damage rather than to relieve symptoms — a point that makes adherence counseling central to pharmacy practice.
The main classes work through distinct mechanisms. Thiazide diuretics promote sodium and water excretion, reducing blood volume. ACE inhibitors (drugs ending in -pril) block conversion of angiotensin I to angiotensin II, causing vasodilation; their characteristic adverse effect is a dry cough, along with hyperkalemia and, rarely, angioedema. Angiotensin II receptor blockers (-sartan) block the same pathway at the receptor and do not cause cough. Calcium channel blockers (-dipine and the non-dihydropyridines verapamil and diltiazem) relax vascular smooth muscle, with dihydropyridines commonly causing peripheral edema. Beta blockers (-olol) reduce heart rate and contractility. Alpha blockers, central alpha-2 agonists, and direct vasodilators fill more specialized roles.
Class selection depends on comorbidity as much as on the blood pressure number. ACE inhibitors and ARBs are favored in diabetes and chronic kidney disease for their renal protection, beta blockers after myocardial infarction and in heart failure, and combinations are common because two drugs at moderate doses often control pressure better than one at maximum dose. ACE inhibitors and ARBs are contraindicated in pregnancy and are not used together.
The PTCE tests antihypertensives within cardiovascular medications, expecting you to match brand and generic names, recognize class suffixes, and know common adverse effects and counseling points. USMLE Step 1 pharmacology approaches the same drugs mechanistically, focusing on receptor targets and side effect profiles. Learning the suffix-to-class mapping first makes both far more manageable.
Key takeaways
- Antihypertensives lower blood pressure to prevent stroke, myocardial infarction, heart failure, and kidney damage.
- Major classes are diuretics, ACE inhibitors, ARBs, calcium channel blockers, and beta blockers.
- Drug suffixes signal class: -pril for ACE inhibitors, -sartan for ARBs, -dipine for dihydropyridine calcium channel blockers, -olol for beta blockers.
- Dry cough is characteristic of ACE inhibitors, while ARBs block the same pathway without it.
- The PTCE tests brand and generic names, classes, and counseling points, while USMLE Step 1 focuses on mechanisms.