Cardizem is a prescription medication used for treating certain types of chest pain (angina). Cardizem is part of a class of drugs called calcium channel blockers that helps slow down the rate at which calcium moves into your heart and blood vessel walls. When using Cardizem you have to check your pulse (heart rate) and your blood pressure daily. Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. Tell your healthcare provider about all other medicines you are taking, including prescription and non-prescription medicines, vitamins, and herbal supplements. It is important that this medication be taken exactly as prescribed by your doctor. Contact your doctor if you experience any side effects like: constipation, diarrhea, dizziness, flushing, headache, heartburn, nausea, unusual tiredness or weakness.