Some people with high blood pressure will only need to take one medicine to control it. But most people with high blood pressure will need to take two or more types of medicine to lower their blood pressure enough.

Why do I need more medicines?

We do not know of any single cause for high blood pressure in most cases. Your blood ­pressure is controlled by a number of different systems in your body. The medicines used to treat high blood pressure act on some of these ­different systems, which means that they work in different ways on your body.

When you start to take a medicine to lower your blood pressure, this medicine will act on one ­system in your body. When this happens, your body may react by using another way to raise your blood pressure again. You may then need to take a second medicine which works on this second way. You will then need to take both medicines to make sure that both systems in your body are being controlled.

Some people with high blood pressure may need to take three or more medicines to control the ­different ways their bodies use to raise their blood pressure.

Can’t my doctor just raise my dose of what I’m taking now?

Raising your dose of one medicine would not work in the same way as taking two medicines. If you just raise your dose of one medicine, this will only control one of the systems in your body. Taking two or more medicines controls your blood pressure in a number of different ways.

Also, taking a higher dose of a medicine increases your chances of having side-effects. Side-effects can be very uncomfortable and you may be tempted to stop taking your medicines. Your doctor may prefer to add another medicine rather than raise your dose for this reason.

How does my doctor decide which medicines to give me?

Finding the right combination of medicines for you can take some trial and error, but there are guidelines that can help your doctor to choose:

If you are under 55 and not of African-Caribbean origin, then you will usually start to take an ACE inhibitor or angiotensin receptor blocker (ARB). If you need to take another medicine, you will be given a calcium-channel blocker or a diuretic. If you need to take three medicines, you will probably take an ACE inhibitor (or ARB), a calcium-channel blocker, and a diuretic.

If you are over 55 or of African-Caribbean origin, then you will usually start to take a calcium-channel blocker or diuretic at first. If you need to take another medicine, you will probably be given an ACE inhibitor (or ARB). If you need to take three medicines, you will probably take an ACE inhibitor (or ARB), a calcium-channel blocker, and a diuretic.

If you need to take more than three medicines, or if you are having side-effects from any of them, then your doctor has other choices. There are other ­medicines available which can also lower blood pressure, but which are not a first-choice treatment.

Is it safe to take all these ­medicines together?

Most blood pressure medicines need to be taken once a day. Because they work in different ways on your body, it should be safe to take them all at the same time.

It can be a good idea to get into the habit of taking all your blood pressure medicines at the same time every day. You may also find that sorting your tablets into a daily pill box can help you remember to take them all.

If you are taking a number of different medicines, it may be useful to ask your pharmacist for a Medicines Use Review (MUR). An MUR is a chance for you to speak with your pharmacist about how you are getting on with your medicines. They can also advise you on how to get the most from your medicines.

Can I take fewer tablets without affecting my blood pressure?

It is possible to reduce the amount of medicines you need to take by making healthy changes to your lifestyle. If you lead a healthy lifestyle this will reduce the amount you will need to lower your blood pressure with medicines. A healthy lifestyle can also help your medicines to work better.

It is also sometimes possible to have two blood pressure medicines in a single tablet. This is sometimes called a combination tablet, and it can reduce the number of tablets you need to take. Combinations are available for some, but not all, blood pressure medicines. Ask your doctor, nurse or pharmacist whether there is a combination tablet that would be appropriate for you.

Combination tablets available in the UK

Published May 2009