Let's take a minute to talk about your medication. 

This is diltiazem, and you should take it exactly as directed by your doctor, at the same time each day. It is a special 'extended release' capsule, so swallow it whole and do not crush, chew or open it. 

Diltiazem helps treat high blood pressure. This is important to reduce your risk of heart attack, stroke, kidney failure or loss of vision. It has other uses, too, like reducing a type of chest pain called 'angina'. 

This medicine is well-tolerated, but some side effects can occur, like headache, feeling flushed or slight swelling in the ankles. It can also cause dizziness, and you can reduce this by standing slowly after sitting or lying down. These effects are normal if they are mild and should go away. If these or other side effects become reasons you want to stop taking this medicine, please talk to your doctor or pharmacist. 

In rare cases, serious side effects can occur, so call your doctor right away if you notice any unusual changes to your body, like fainting, chest pain, rash, shortness of breath or fatigue. 

To reduce side effects, you should ask your doctor or pharmacist before taking any new medicines, even if they don't require a prescription. 

For best results, keep taking diltiazem, because it is helping you control your blood pressure or angina. And, follow your doctor's advice for checking your blood pressure and heart rate.