Terazosin - an alpha-blocker

About terazosin

Terazosin belongs to a group of medicines known as alpha-blockers. It works by blocking the action of certain nerve impulses. This blocking action is useful in two different medical conditions. It is used to help control the symptoms of prostate gland enlargement in men, and it is also prescribed to reduce high blood pressure in people with hypertension.

The prostate gland commonly becomes larger in older men. Prostate gland enlargement is also called benign prostatic hyperplasia (BPH). The prostate gland is situated close to the bladder, so its enlargement can cause problems with passing urine. Common symptoms that are experienced are having to wait before your urine starts to flow, taking longer at the toilet, dribbling urine, and a feeling that your bladder is not quite empty. Terazosin works by relaxing the muscles around your bladder and prostate gland so that you can pass urine more easily.

Terazosin works in high blood pressure by widening (relaxing) blood vessel walls. This lowers your blood pressure and allows blood to circulate more freely around your body.

Before taking terazosin

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking terazosin it is important that your doctor knows:

• If you ever feel dizzy or faint when you stand up, or if you have ever fainted after passing urine.

• If you need to have cataract eye surgery.

• If you are pregnant or breastfeeding.

• If you have ever had an allergic reaction to a medicine.

• If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

How to take terazosin

• Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about terazosin and will provide you with a full list of the side-effects which you may experience from taking it.

• Take terazosin exactly as your doctor tells you to. Swallow the tablet with a drink of water. You can take terazosin either before or after a meal.

• There are several strengths of terazosin tablet available: 1 mg, 2 mg, 5 mg, and 10 mg. When you first start the treatment, your doctor may give you a low dose which will then later be increased. This allows your doctor to make sure that you have the dose that helps your condition and avoids any unwanted symptoms.

• Your first dose of terazosin may make you feel dizzy or faint, so it is important that you take it just before you go to bed. If you feel dizzy or weary, or if you start sweating, remain lying down until these symptoms have completely gone.

• Take terazosin once every day. After the first dose, you can take your dose at a time of day that best suits you. You should, however, try to take your doses at the same time of day each day, as this will help you to remember to take the tablets regularly.

• If you forget to take a dose, take it as soon as you remember. If you do not remember until the following day, skip the forgotten dose. Do not take two doses at the same time to make up for a missed dose.

Getting the most from your treatment

• Terazosin can cause dizziness, particularly when you first start taking it. This may affect your ability to drive. Make sure your reactions are normal before you drive or do things which would be dangerous if you were not fully alert.

• Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress. Your doctor is likely to want to take your blood pressure from time to time, particularly when you first start the treatment.

• You are advised not to drink alcohol while you are on terazosin. Alcohol increases the risk of side-effects from terazosin, such as feeling faint or dizzy.

• If you are taking terazosin for urinary symptoms, consider reducing or stopping the amount of caffeine you drink (commonly found in tea, coffee and cola). Caffeine can make your symptoms worse, so drinking less of these things may benefit you. Also, if you are a smoker, stopping smoking may significantly improve your symptoms. This is because nicotine irritates the bladder. You can ask your doctor for advice on quitting.

• If you are having an operation or dental treatment, tell the person carrying out the treatment that you are taking terazosin. This is because your blood pressure may drop suddenly if you have an anaesthetic. If you are having cataract surgery, it is particularly important that you tell your surgeon you are on terazosin. This is because an eye problem known as 'floppy iris syndrome' has developed in some people and your doctor may advise you to stop taking terazosin for a short while.

• If you buy any medicines check with a pharmacist that they are suitable to take with your other medicines. Some painkillers called non-steroidal anti-inflammatory drugs (NSAIDs) can reduce the blood pressure-lowering effect of terazosin.

Can terazosin cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with terazosin. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

If you experience any other symptoms which you think may be due to the tablets, speak with your doctor or pharmacist for further advice.

How to store terazosin

• Keep all medicines out of the reach and sight of children.

• Store in a cool, dry place, away from direct heat and light.

Important information about all medicines