Amlodipine Drug Review: PTCB Exam Prep Guide

Amlodipine Overview for the PTCB Exam

Amlodipine is one of the most commonly prescribed antihypertensive medications and a frequent topic on the PTCB certification exam. As a pharmacy technician, you will dispense amlodipine regularly in community pharmacy settings. This comprehensive drug review will help you master the key facts needed for exam day.

Brand Name and Classification

Amlodipine is sold under the brand name Norvasc. It belongs to the dihydropyridine calcium channel blocker (CCB) class. Dihydropyridine CCBs are identified by the suffix -dipine. Other drugs in this subclass include nifedipine (Procardia) and felodipine (Plendil). Non-dihydropyridine CCBs include verapamil (Calan) and diltiazem (Cardizem), which have different clinical profiles.

Mechanism of Action

Amlodipine blocks L-type calcium channels in vascular smooth muscle, preventing calcium influx and causing vasodilation. This reduces peripheral vascular resistance and lowers blood pressure. Unlike non-dihydropyridine CCBs, amlodipine primarily affects blood vessels rather than the heart, so it does not significantly slow heart rate or reduce cardiac contractility.

Common Indications

Hypertension: First-line treatment option for high blood pressure
Chronic stable angina: Reduces frequency of anginal episodes
Vasospastic (Prinzmetal) angina: Prevents coronary artery spasm

Dosing Information

Amlodipine is available in 2.5 mg, 5 mg, and 10 mg tablets. The typical starting dose is 5 mg once daily, with a maximum dose of 10 mg daily. For elderly patients or those with hepatic impairment, the recommended starting dose is 2.5 mg once daily. Amlodipine has a long half-life of 30 to 50 hours, allowing for once-daily dosing.

Side Effects

The most characteristic side effect of amlodipine, and one frequently tested on the PTCB exam, is peripheral edema (ankle swelling). Other side effects include:

Headache: Common, especially when starting therapy
Dizziness: Related to blood pressure reduction
Flushing: Due to vasodilation
Fatigue: Usually mild and transient
Gingival hyperplasia: Overgrowth of gum tissue with long-term use

Drug Interactions

CYP3A4 inhibitors: Ketoconazole and erythromycin may increase amlodipine levels
Simvastatin: Amlodipine increases simvastatin levels; simvastatin should not exceed 20 mg daily when combined
Cyclosporine: Amlodipine may increase cyclosporine levels

PTCB Exam Tips

Key facts: amlodipine is brand Norvasc, dihydropyridine CCBs end in -dipine, the hallmark side effect is peripheral edema, and it does not significantly affect heart rate (unlike verapamil and diltiazem). Know the difference between dihydropyridine and non-dihydropyridine CCBs for the exam.

Practice identifying drug classes with our Top 200 Drugs flashcards and strengthen your skills with PTCB practice questions.