Antihypertensive Drug Classes: PTCB Pharmacology Review

Blood Pressure Medications on the PTCE

Hypertension is the most common chronic condition in the United States, and antihypertensive medications are among the most frequently prescribed drug classes. The PTCE expects you to know drug classes, representative examples, mechanisms, and key side effects.

ACE Inhibitors (-pril)

Mechanism: Block angiotensin-converting enzyme, reducing angiotensin II production. Examples: lisinopril (Zestril, Prinivil), enalapril (Vasotec), ramipril (Altace), benazepril (Lotensin). Key side effects: dry cough (most common reason for switching), hyperkalemia, angioedema (rare but serious). Contraindicated in pregnancy.

ARBs (-sartan)

Mechanism: Block angiotensin II at the receptor. Examples: losartan (Cozaar), valsartan (Diovan), irbesartan (Avapro), olmesartan (Benicar). Similar to ACE inhibitors but without the cough. Also contraindicated in pregnancy.

Beta-Blockers (-olol)

Mechanism: Block beta-adrenergic receptors, reducing heart rate and cardiac output. Examples: metoprolol (Lopressor, Toprol XL), atenolol (Tenormin), propranolol (Inderal), carvedilol (Coreg). Key side effects: bradycardia, fatigue, bronchospasm (avoid in severe asthma), masking hypoglycemia symptoms in diabetics. Do not stop abruptly (rebound hypertension).

Calcium Channel Blockers

Two subtypes:

Dihydropyridines (-dipine): amlodipine (Norvasc), nifedipine (Procardia). Primarily vasodilators. Side effects: peripheral edema, flushing, headache.
Non-dihydropyridines: diltiazem (Cardizem), verapamil (Calan). Also reduce heart rate. Constipation is a common side effect of verapamil.

Diuretics

Thiazides: hydrochlorothiazide (HCTZ), chlorthalidone. First-line for many patients. Watch for hypokalemia, hyperglycemia, hyperuricemia.
Loop diuretics: furosemide (Lasix), bumetanide (Bumex). More potent. Risk of ototoxicity at high doses.
Potassium-sparing: spironolactone (Aldactone), triamterene. Risk of hyperkalemia.

Review these classes thoroughly with PTCB flashcards and practice identifying the right class for each scenario.