What should you know about prescription blood pressure medication?

High blood pressure often causes no clear symptoms, so a prescription is usually based on repeated readings and your overall health rather than how you feel on a particular day. Medicines may relax blood vessels, reduce fluid retained by the body, or slow the heart. The aim is to lower the chance of damage involving the heart, brain, kidneys, and eyes. [Hypertension](/conditions/hypertension/) is commonly monitored with home readings or [Ambulatory Blood Pressure Monitoring](/treatments/diagnostics-and-screening/ambulatory-blood-pressure-monitoring/).

Take the medicine at the same time each day according to the label. Do not double a dose after forgetting one; check the instructions or ask a pharmacist. Stand up carefully if you feel dizzy, and record readings alongside symptoms so the prescriber can adjust treatment safely. Discuss salt intake, alcohol, exercise, and other medicines, including anti-inflammatory painkillers and cold remedies. Do not stop treatment because a reading improves: that may show the medicine is working.

Get urgent help for sudden weakness or numbness on one side, facial drooping, speech difficulty, severe chest pain, severe breathlessness, fainting, or a sudden severe headache. These can signal an emergency such as [Stroke](/conditions/stroke/) or [Angina](/conditions/angina/). Contact your prescriber promptly for persistent dizziness, swelling, troublesome palpitations, or readings that remain unexpectedly high.

Ask what your medicine does, when to take it, what a missed dose means, and which readings should prompt a call. Ask how often your kidney function or other checks are needed and whether treatment also relates to a previous [Transient Ischaemic Attack](/conditions/transient-ischaemic-attack/).