Verapamil

ATC code

C08DA01

Therapeutic class

Non-dihydropyridine calcium channel blocker · Phenylalkylamine derivative

Forms

oral tablet, extended-release oral tablet, injectable solution

Brand names

Manidon HTA (ES) · Calan (US) · Verelan (US) · Isoptin (DE)

Overall confidence

medium

Regulatory sources consulted

aemps-cima-ft-58369
CredibleMeds.org
Flockhart Table (cyp-interactions)
RxNorm rxcui 11170 ↗

Approved indications

Essential hypertension.
Ischemic heart disease: Chronic stable angina, unstable angina, vasospastic (Prinzmetal's) angina.
Cardiac arrhythmias: Paroxysmal supraventricular tachycardia, atrial fibrillation/flutter with rapid ventricular response (except in pre-excitation syndromes).

Contraindications

Absolute

Cardiogenic shock.
Second- or third-degree AV block (without a functioning pacemaker).
Sick sinus syndrome (without a functioning pacemaker).
Heart failure with reduced ejection fraction (<35%).
Atrial fibrillation/flutter with an accessory bypass tract (e.g., WPW, LGL syndromes).
Concomitant use with ivabradine or dabigatran.

Clinical warnings

Major warning · Heart Failure: May worsen heart failure in patients with left ventricular dysfunction due to its negative inotropic effects. — AEMPS CIMA
Hypotension: May cause symptomatic hypotension. — AEMPS CIMA
Major warning · Hepatic Injury: Elevations of transaminases and cases of liver injury have been reported. Monitor liver function. — AEMPS CIMA

Drug interactions

HighDabigatranB01AE07
Mechanism: Inhibition of P-glycoprotein (P-gp) by verapamil, increasing dabigatran exposure and bleeding risk.
Recommendation: Concomitant use is contraindicated.
AEMPS CIMA FT 58369
HighSimvastatinC10AA01
Mechanism: Inhibition of simvastatin metabolism via CYP3A4 by verapamil, significantly increasing statin AUC and risk of myopathy/rhabdomyolysis.
Recommendation: Limit simvastatin dose to 10 mg/day or use a statin not metabolized by CYP3A4 (e.g., pravastatin, rosuvastatin).
FDA Drug LabelPMID:11144992
HighDigoxinC01AA05
Mechanism: Inhibition of P-glycoprotein (P-gp) at the renal tubule by verapamil, reducing digoxin clearance and increasing its serum levels.
Recommendation: Reduce digoxin dose by 50% when starting verapamil and monitor serum digoxin levels.
PMID:6336794

Adverse events

Common (≥1%)

constipation · headache · dizziness · bradycardia · hypotension · peripheral edema · flushing

Rare but serious

complete atrioventricular block · congestive heart failure · hepatotoxicity · paralytic ileus · gingival hyperplasia

Pregnancy and lactation

FDA category: C

Not recommended during pregnancy unless strictly necessary. It is excreted in breast milk; the benefit to the mother must be weighed against the risk to the infant.