Key takeaways
Diltiazem (Cardizem) and verapamil ER (Verelan) are both calcium channel blockers (CCBs) but are used for different conditions. Diltiazem (Cardizem) is primarily used to treat chest pain (angina) and is taken four times a day, while Verapamil ER (Verelan) is used to treat high blood pressure and is taken once daily. Diltiazem (Cardizem) can be crushed or chewed, whereas verapamil ER (Verelan) capsules can be opened and mixed with applesauce if swallowing is difficult. Common side effects of diltiazem include swelling in the legs, dizziness, and tiredness, while verapamil ER can cause constipation, headache, and dizziness. Both medications can cause low blood pressure and heart rhythm problems, but verapamil ER has additional risks for people with certain heart conditions. Diltiazem (Cardizem) is available as a lower-cost generic option, and verapamil ER also has a generic form.
