Verapamil

Non-DHP CCB·Cardiovascular - Antihypertensives

Hypertension, angina, SVT termination, AF rate control

PBSNON-DHP CCBIsoptin, Isoptin SR, Veracaps SR40 mg tabletS4+1

Max Dose

480 mg/day

Half-life

3–7 h

Constipation

HIGH

Heart Block

AVOID

Rapid Summary

Overview

Non-dihydropyridine CCB. Exerts potent negative inotropic and negative chronotropic effects. Acts heavily on the AV node.

Maximum Dose

Max 480 mg/day (usually divided or as SR).

Clinical Focus

NEVER co-administer with beta-blockers due to the risk of fatal complete heart block and asystole.

Bottom Line

Verapamil is the preferred CCB for rate control in AF/SVT, but must never be combined with beta-blockers due to risk of fatal bradycardia and AV block.

Formulation & Access

Brand Names

Isoptin, Isoptin SR, Veracaps SR

Oral Routes

Tablets (40 mg, 80 mg). SR Tablets (180 mg, 240 mg).

Parenteral

Ampoule (5 mg/2 mL) for IV use.

Indications & Use

Primary

PBSTGA

Hypertension, angina, SVT termination, AF rate control.

Off-Label

OFF

Cluster headache prophylaxis.

Clinical Place

Alternative to beta-blockers for rate control in AF, especially in asthmatic patients.

Quick reference

Class & Role

Non-DHP CCB — Non-dihydropyridine CCB.

Route / Formulation

Tablets (40 mg, 80 mg). SR Tablets (180 mg, 240 mg). (Isoptin, Isoptin SR, Veracaps SR)

Usual Dose & Max

PO 160-240 mg/day in divided doses, or 180-240 mg SR OD. Max 480 mg/day.

Key Indication Doses

Hypertension / Angina: PO 160-240 mg/day in divided doses, or 180-240 mg SR OD. Max 480 mg/day. SVT / AF Rate Control: PO 40-120 mg TDS. Acute SVT (IV): IV 5-10 mg over 2-3 mins under continuous ECG and BP monitoring. (Specialist only).

Best Uses

Verapamil is the preferred CCB for rate control in AF/SVT, but must never be combined with beta-blockers due to risk of fatal bradycardia and AV block.

Avoid / Cautions

Heart failure with reduced ejection fraction (HFrEF), 2nd/3rd degree AV block, WPW syndrome with AF, sick sinus syndrome. Pregnancy Category C.

Key Risks

Cardiovascular: Bradycardia, AV block, worsening of HFrEF, hypotension. Gastrointestinal: Severe constipation (especially in the elderly). Neurological: Dizziness, headache.

Key Interactions

Beta-blockers (oral or IV). The combination leads to profound bradycardia, complete heart block, and cardiogenic shock. Moderate CYP3A4 inhibitor. Massively increases levels of Simvastatin/Atorvastatin (myopathy risk) and Digoxin.

Monitoring

Baseline and ongoing ECG to ensure PR interval is normal. Monitor HR and BP. LFTs (hepatic clearance) and monitor interacting drug levels (e.g., TDM for Digoxin).

Clinical Pearl

Constipation is extremely common and dose-limiting in older adults. Proactively prescribe a laxative if starting high doses.

Access

Isoptin, Isoptin SR, Veracaps SR40 mg tablet

Brand: Isoptin, Isoptin SR, Veracaps SR
Formulation: Tablets (40 mg, 80 mg)

Verapamil

Non-DHP CCB·Cardiovascular - Antihypertensives

Hypertension, angina, SVT termination, AF rate control

PBSNON-DHP CCBIsoptin, Isoptin SR, Veracaps SR40 mg tabletS4+1

Max Dose

480 mg/day

Half-life

3–7 h

Constipation

HIGH

Heart Block

AVOID

Rapid Summary

Overview

Non-dihydropyridine CCB. Exerts potent negative inotropic and negative chronotropic effects. Acts heavily on the AV node.

Maximum Dose

Max 480 mg/day (usually divided or as SR).

Clinical Focus

NEVER co-administer with beta-blockers due to the risk of fatal complete heart block and asystole.

Bottom Line

Verapamil is the preferred CCB for rate control in AF/SVT, but must never be combined with beta-blockers due to risk of fatal bradycardia and AV block.

Formulation & Access

Brand Names

Isoptin, Isoptin SR, Veracaps SR

Oral Routes

Tablets (40 mg, 80 mg). SR Tablets (180 mg, 240 mg).

Parenteral

Ampoule (5 mg/2 mL) for IV use.

Indications & Use

Primary

PBSTGA

Hypertension, angina, SVT termination, AF rate control.

Off-Label

OFF

Cluster headache prophylaxis.

Clinical Place

Alternative to beta-blockers for rate control in AF, especially in asthmatic patients.

Quick reference

Class & Role

Non-DHP CCB — Non-dihydropyridine CCB.

Route / Formulation

Tablets (40 mg, 80 mg). SR Tablets (180 mg, 240 mg). (Isoptin, Isoptin SR, Veracaps SR)

Usual Dose & Max

PO 160-240 mg/day in divided doses, or 180-240 mg SR OD. Max 480 mg/day.

Key Indication Doses

Best Uses

Verapamil is the preferred CCB for rate control in AF/SVT, but must never be combined with beta-blockers due to risk of fatal bradycardia and AV block.

Avoid / Cautions

Heart failure with reduced ejection fraction (HFrEF), 2nd/3rd degree AV block, WPW syndrome with AF, sick sinus syndrome. Pregnancy Category C.

Key Risks

Cardiovascular: Bradycardia, AV block, worsening of HFrEF, hypotension. Gastrointestinal: Severe constipation (especially in the elderly). Neurological: Dizziness, headache.

Key Interactions

Monitoring

Baseline and ongoing ECG to ensure PR interval is normal. Monitor HR and BP. LFTs (hepatic clearance) and monitor interacting drug levels (e.g., TDM for Digoxin).

Clinical Pearl

Constipation is extremely common and dose-limiting in older adults. Proactively prescribe a laxative if starting high doses.

Access

Isoptin, Isoptin SR, Veracaps SR40 mg tablet

Brand: Isoptin, Isoptin SR, Veracaps SR
Formulation: Tablets (40 mg, 80 mg)