What are the indications for Verapamil (calcium channel blocker)?

Indications for Verapamil

Verapamil is primarily indicated for the rapid conversion of paroxysmal supraventricular tachycardias and temporary control of rapid ventricular rate in atrial flutter or atrial fibrillation, as well as for the treatment of hypertension. 1, 2

Cardiovascular Indications

Arrhythmia Management

• Supraventricular Tachycardias (SVT)

  • First-line treatment for stable, narrow-complex tachycardias if rhythm remains uncontrolled or unconverted by adenosine or vagal maneuvers 3
  • Rapid conversion to sinus rhythm of paroxysmal SVT, including those associated with accessory bypass tracts 1
  • Should be administered at 2.5 to 5 mg IV over 2 minutes; may repeat as 5 to 10 mg every 15 to 30 minutes to total dose of 20 to 30 mg 3

• Atrial Fibrillation/Flutter

  • Temporary control of rapid ventricular rate in atrial flutter or atrial fibrillation 1
  • Used for ventricular rate control in patients with atrial fibrillation or atrial flutter 3
  • Conversion of atrial flutter or fibrillation to sinus rhythm is uncommon (about 10%) 1

Hypertension

• Treatment of hypertension to lower blood pressure and reduce risk of fatal and nonfatal cardiovascular events 2
• Effective first-line treatment for patients with mild to moderate essential hypertension 4
• More effective in patients with higher pretreatment blood pressure and potentially more pronounced effect in older patients 4

Angina

• Management of angina pectoris, including vasospastic angina 5, 6
• Effective in Prinzmetal's variant angina, unstable angina, and chronic stable angina 6

Important Contraindications and Precautions

• Contraindicated in:

  • Patients who have taken beta-blockers due to risk of profound bradycardia and hypotension 3
  • SVTs associated with Wolff-Parkinson-White syndrome, as it may precipitate VT/VF 3
  • Patients with significant left ventricular dysfunction 5
  • Increased risk for cardiogenic shock 5
  • Second or third-degree atrioventricular block without a cardiac pacemaker 5

• Use with caution in:

  • Patients with severe disabling symptoms and markedly elevated pulmonary arterial pressure in combination with marked outflow obstruction 3
  • Patients with obstructive hypertrophic cardiomyopathy in the setting of systemic hypotension or severe dyspnea at rest 3

Administration Considerations

• For SVT, verapamil should be administered after appropriate vagal maneuvers have been attempted 1
• Initial use of verapamil injection should, if possible, be in a treatment setting with monitoring and resuscitation facilities 1
• Calcium gluconate can be used to prevent or reverse hypotension associated with verapamil administration without altering its antiarrhythmic effect 7
• For hypertension, sustained-release formulations are available for once-daily dosing with equivalent efficacy to conventional formulations given three times daily 4

Clinical Advantages and Considerations

• May be preferred over beta-blockers in patients with asthma or chronic obstructive airway disease 4
• Does not cause reflex tachycardia, orthostatic hypotension, or development of tolerance 4
• Produces marked blood pressure reductions when combined with diuretics, ACE inhibitors, beta-blockers, and vasodilators 4
• Common side effects include constipation, hypotension, bradycardia, and leg edema 5

Verapamil's unique pharmacological profile as a non-dihydropyridine calcium channel blocker makes it particularly valuable for managing both arrhythmias and hypertension, with specific advantages in certain patient populations where beta-blockers may be contraindicated.