Isoptin (Verapamil) Detailed Information

The active ingredient in Isoptin is **Verapamil**. Inactive ingredients may include magnesium stearate, lactose, microcrystalline cellulose, and povidone, depending on the formulation.

Common side effects of Isoptin include:

• Dizziness or lightheadedness
• Constipation
• Headache
• Nausea
• Fatigue

Less common but serious side effects include:

• Slow or irregular heartbeat
• Swelling of the feet or ankles
• Severe dizziness or fainting
• Shortness of breath
• Severe allergic reactions (swelling of the face, lips, or throat)

Contact your doctor if you experience severe or persistent side effects.

Isoptin is usually taken once or twice daily, with or without food. It is important to take it at the same time each day for maximum effectiveness. Follow your doctor’s dosage instructions carefully and do not stop taking the medication without medical advice.

Isoptin can interact with other medications, including:

• Beta-blockers: Can enhance the effects on heart rate and blood pressure.
• Diuretics: May increase blood pressure-lowering effects.
• Digoxin: Can increase the risk of heart rhythm problems.
• Grapefruit juice: Can alter Verapamil levels in the blood.

Always inform your healthcare provider about all medications and supplements you take.

Isoptin starts working within **1 to 2 hours** after ingestion, with full therapeutic effects occurring over several days of consistent use.

Seek medical help immediately if you experience:

• Severe dizziness or fainting
• Slow or irregular heartbeat
• Swelling in the legs or feet
• Severe shortness of breath
• Signs of an allergic reaction