Verapamil is a calcium channel blocker used primarily to treat high blood pressure, chest pain (angina), and certain heart rhythm disorders (arrhythmias). It works by relaxing the muscles of your heart and blood vessels, which helps to lower blood pressure, reduce the workload on the heart, and increase the supply of blood and oxygen to the heart.
Uses:
- Hypertension (High Blood Pressure): Verapamil helps to lower blood pressure, reducing the risk of strokes, heart attacks, and kidney problems.
- Angina Pectoris: It is used to manage chronic stable angina and vasospastic angina (Prinzmetal’s or variant angina).
- Arrhythmias: Verapamil is effective in treating certain types of irregular heartbeats, particularly supraventricular tachycardia.
- Migraine Prevention: Sometimes used off-label for the prevention of migraines.
Mechanism of Action:
Verapamil inhibits the influx of calcium ions through L-type calcium channels in cardiac and vascular smooth muscle. This results in:
- Vasodilation: Relaxation of blood vessels, leading to reduced peripheral resistance and blood pressure.
- Negative Inotropic Effect: The decreased force of heart contractions.
- Negative Chronotropic Effect: Slowed heart rate.
- Negative Dromotropic Effect: Slowed conduction through the AV node, which is useful in treating certain arrhythmias.
Dosage:
- Immediate-Release Tablets: Typically taken 3-4 times a day.
- Extended-Release Tablets: Usually taken once or twice a day.
- Dosage varies based on the condition being treated, the patient’s response, and other factors. Take the prescribed dosage as directed by your physician.
Side Effects:
Common side effects may include:
- Constipation
- Dizziness
- Headache
- Nausea
- Fatigue
- Edema (swelling of the ankles or feet)
Serious side effects that require immediate medical attention:
- Severe dizziness or fainting
- Shortness of breath
- Swelling of the hands, feet, or ankles
- Very slow heart rate (bradycardia)
- Heart failure symptoms (e.g., unusual tiredness, weight gain)
Contraindications:
- Severe left ventricular dysfunction
- Hypotension (low blood pressure)
- Sick sinus syndrome or second- or third-degree AV block (unless a pacemaker is present)
- Atrial fibrillation or flutter with an accessory bypass tract: (e.g., Wolff-Parkinson-White syndrome)
Drug Interactions:
Verapamil can interact with various medications, including:
- Beta-blockers: Increased risk of bradycardia and heart failure.
- Digoxin: Increased digoxin levels.
- Statins (e.g., simvastatin, lovastatin): Increased risk of myopathy.
- Cyclosporine: Increased cyclosporine levels.
- Rifampin: Decreased verapamil levels.
Precautions
- Dosage adjustments May be required for patients with liver or kidney disease.
- Use during Pregnancy and breastfeeding only if prescribed by a doctor.
- Elderly Patients: May be more sensitive to the effects of verapamil.
Discuss your health concerns with a medical professional for the best treatment plan.