What should you know about most common blood pressure medicine?

ACE inhibitors and angiotensin receptor blockers relax blood vessels by affecting hormone signals. Calcium channel blockers widen arteries and may slow the heart. Diuretics help the body remove extra salt and water. One medicine may be enough, while some people need a combination.

A prescription is based on repeated blood pressure readings, kidney function, other conditions and medicines you already take. An ambulatory blood pressure monitor can record readings during normal activities and sleep, helping clarify the pattern.

Take the medicine at the prescribed time and do not stop it suddenly without medical advice. Keep a record of home readings and symptoms. Dizziness, ankle swelling, a persistent cough or changes in urination should be reported because the dose or medicine may need review. Avoid adding over-the-counter pain medicines or supplements without checking first.

Seek emergency help for chest pressure, severe breathlessness, fainting, new weakness on one side, trouble speaking or a sudden severe headache. These can signal a serious problem such as angina or stroke, whether or not you take blood pressure medicine.

Ask which medicine is being prescribed, what improvement to expect, when to check your pressure, and which side effects need a same-day call. Ask whether kidney or blood tests are needed and what to do if you miss a dose.