context: Calcium channel blockers are prescription medications that relax blood vessels and increase the supply of blood and oxygen to the heart while also reducing the heart's workload. Examples of calcium channel blockers include: Amlodipine ( Norvasc) Bepridil ( Vascor) Diltiazem ( Cardizem, Cardizem CD, Cardizem SR, Dilacor XR, Diltia XT, Tiazac) Felodipine ( Plendil) Nicardipine ( Cardene, Cardene SR) Nifedipine ( Adalat, Adalat CC, Procardia, Procardia XL) Nisoldipine, ( Sular) Verapamil ( Calan, Calan SR, Covera- HS, Isoptin, Isoptin SR, Verelan, Verelan PM) Caduet is a combination of a statin cholesterol drug and amlodipine. Heart conditions that calcium channel blockers might be prescribed for: High blood pressure (especially in African Americans) Coronary artery disease Coronary spasm Angina (chest pain) Abnormal heart rhythms Hypertrophic cardiomyopathy Diastolic heart failure (preserved left ventricular function) Raynaud's syndrome (a circulatory problem affecting blood vessels in the hands and feet) Pulmonary hypertension (high blood pressure in the arteries of your lungs) If you have systolic heart failure, then amlodipine and felodipine are the only calcium channel blockers you should use. Calcium channel blockers can also prevent migraine headaches. Calcium channel blockers should be taken with food or milk. Follow the label directions on how often to take it. The number of doses you take each day, the time allowed between doses, and how long you need to take it will depend on the type of medication your doctor prescribed and why. You should check your blood pressure regularly. Ask your doctor how often. You may need to take and record your pulse daily. If it's slower than your doctor said it should be, call your doctor or nurse to find out if you should still take your calcium channel blocker that day. Side effects of calcium channel blockers can include: Lightheadedness Low blood pressure Slower heart rate Drowsiness Constipation Swelling of feet ankles and legs Increased appetite. Gastroesophageal reflux disease ( GERD) Tenderness or bleeding of the gums Sexual dysfunction Let your doctor know if these side effects are severe or don't go away. Contact your doctor right away if you: Gain weight Have trouble breathing (shortness of breath, coughing, or wheezing) Get a skin rash or hives Are very lightheaded or faint Do not eat grapefruit or drink grapefruit juice while you're taking a calcium channel blocker. Avoid alcohol because it can change how calcium channel blockers work and make the side effects worse. Your doctor needs to know about all the medications you're taking, to avoid problems with calcium channel blockers. Talk to your doctor before you take anything new, including over-the-counter drugs, herbs, and supplements. Calcium channel blockers can be used during pregnancy to manage high blood pressure and preeclampsia. However, you should always consult with your doctor before taking calcium channel blockers during pregnancy. These drugs may pass into breast milk, but no adverse effect on breastfed infants has been found. Discuss the risks and benefits of using calcium channel blockers while breastfeeding with your doctor. The safety of calcium channel blockers in children has not been established; however, no problems have been found to date. Discuss the risks and benefits of giving your child calcium channel blockers with your child's doctor. Older adults have more side effects from calcium channel blockers than younger people. Doctors usually prescribe lower doses.