Prazosina - um bloqueador alfa

About prazosin

O prazosin pertence a um grupo de medicamentos conhecidos como bloqueadores alfa. Funciona bloqueando a ação de certos impulsos nervosos. Essa ação de bloqueio é útil em várias condições médicas listadas na tabela acima, embora seja geralmente usada para tratar pressão alta (hipertensão).

O prazosina funciona em pessoas com hipertensão ou com insuficiência cardíaca, by relaxing blood vessels. This allows blood and oxygen to circulate more freely around your body, lowering blood pressure and reducing strain on your heart.

A glândula prostática comumente aumenta em homens mais velhos. O aumento da glândula prostática também é chamado de hiperplasia prostática benigna (HPB). 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. Prazosin works by relaxing the muscles around your bladder and prostate gland so that you can pass urine more easily.

Em Doença de Raynaud, prazosin relaxes the blood vessels in your hands so that blood can reach your fingers more easily. This helps to prevent coldness and stiffness.

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 prazosin it is important that your doctor knows:

• Se você já se sentiu tonto ou desmaiou ao se levantar, ou se já desmaiou após urinar.

• If you need to have cataract eye surgery.

• Se você está grávida ou amamentando.

• Se você tiver algum problema com o funcionamento do seu fígado, ou qualquer problema com o funcionamento dos seus rins.

• Se você já teve uma reação alérgica a um medicamento.

• Se você estiver tomando ou usando qualquer outro medicamento. Isso inclui quaisquer medicamentos que você esteja tomando e que estejam disponíveis para compra sem receita médica, bem como medicamentos fitoterápicos e complementares.

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

• Your doctor will tell you how many tablets to take each day. This can range from 2-4 tablets a day depending upon the reason why you have been prescribed prazosin. Take the tablets exactly as your doctor tells you to.

• Swallow the tablet with a drink of water. You can take prazosin either before or after a meal, but you should try to take your doses at the same times of day each day. This will help you to remember to take the tablets regularly.

• Your first dose of prazosin 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.

• There are several strengths of prazosin tablet available: 500 micrograms, 1 mg, 2 mg, and 5 mg. When you first start the treatment, your doctor will give you a low dose which may 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.

• Se você esquecer de tomar uma dose, tome-a assim que se lembrar, a menos que esteja quase na hora da próxima dose, nesse caso, pule a dose esquecida. Não tome duas doses juntas para compensar uma dose esquecida.

• Prazosin 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 prazosin. Alcohol increases the risk of side-effects from prazosin, such as feeling faint or dizzy.

• If you are taking prazosin 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 prazosin. 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 prazosin. 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 prazosin for a short while.

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

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 prazosin. 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.

Se você sentir quaisquer outros sintomas que acha que podem ser causados pelos comprimidos, fale com seu médico ou farmacêutico para mais orientações.

• Mantenha todos os medicamentos fora do alcance e da vista das crianças.

• Armazene em local fresco e seco, longe de calor e luz diretos.