Name

nifedipine (Procardia®)

Class

Calcium channel blocker

Description/Mechanism

Nifedipine inhibits the movement of calcium ions across cell membranes. By blocking the entry of calcium into cells, smooth muscle contraction is depressed. Nifedipine dilates coronary arteries and arterioles in normal and ischemic tissue, prevents coronary artery spasm, dilates peripheral vessels, and decreases total peripheral resistance (lessening myocardial oxygen demand). When arterial pressure is reduced, a reflex is stimulated, causing a small increase in heart rate, and a mild elevation in the force of myocardial contraction. Nifedipine does not slow SA nodal activity or prolong AV nodal conduction.

Onset

15-30 minutes

Duration

6-8 hours

Indications

Angina pectoris

Hypertensive Crisis

Contraindications

Hypersensitivity

Compensatory hypertension

Hypotension

Adverse Reactions

Dizziness

Lighteadedness

Flushing

Heat sensation

Hypotension

Drug Interactions

Beta blockers may potentiate effects

Antihypertensives may potentiate hypotensive effects

Effects of theophylline may be increased.

Supplied

Soft Gelatin capsules: 10, 20 mg.

Extended release tablets: 30, 60, 90 mg

Dose/Administration

Have patient bite and swallow.

Adult

10 mg, may repeat in 30 min

Pediatric

Not recommended.

Special Consideration

Pregnancy Safety: Category C

A beta blocker should be available for management of reflex tachycardia.

May produce hypotension and precipitate angina pectoris in elderly patients.