Doxazosin is used on its own or together with other medicines to keep your blood pressure under control. It lowers blood pressure by relaxing the blood vessels.
This medicine is also used to treat symptoms of an enlarged prostate gland in men known as benign prostatic hyperplasia (BPH).
An enlarged prostate gland may cause problems such as difficulty in passing urine, slow or interrupted flow of urine, frequent urination, and dribbling after passing urine. This medicine helps relax the muscles in the prostate gland and bladder to allow the urine to pass more easily.
Take Doxazosin exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.
You may take this medicine with or without food. Try to take it at the same time each day.
Doxazosin is available as a conventional tablet or as an extended-release tablet.
If you are taking the extended-release type of tablet (usually labelled as "XL"), swallow it whole. Do not divide, chew, or crush the tablet.
The dose of this medicine will be decided by your doctor. Your doctor will advise you on the treatment timeframe depending on your condition and response to the medication.
Doxazosin must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed by the doctor.
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.
DO NOT double a dose under any circumstances.
If you often forget to take your medicine, let your doctor and pharmacist know.
Alert your doctor if you have the following conditions:
- history of orthostatic hypotension (fall in blood pressure when standing up from a sitting or lying down position)
- history of obstruction in the oesophagus (food pipe), stomach or bowel
- enlarged prostate gland and have low blood pressure
- enlarged prostate gland with a congested or blocked urinary tract, long-term urinary tract infection, or bladder stones
- bladder disorders with or without kidney problems
as Doxazosin may not be suitable for you.
Inform your doctor if you have the following conditions:
- heart problems e.g. chest pain, recent heart attack, heart failure
- long-term constipation
- liver disease
Let your doctor know if you are pregnant or breastfeeding.
Be sure to check with your doctor or pharmacist before giving Doxazosin to the elderly. Elderly people may be more sensitive to the side effects.
If you are taking the extended-release form of Doxazosin, you may see a small tablet-shaped casing in your bowel. This is normal, do not be alarmed. This casing is just an empty shell; the medicine inside it has already been absorbed by your body.
If you are going to have an eye operation, particularly cataract surgery, inform your doctor that you are taking this medicine.
Why is it important to keep my appointments with the doctor?
Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly.
- Your blood pressure may fall to unsafe levels without you noticing it. Monitor your blood pressure regularly during treatment.
- Routine tests (e.g. liver function, complete blood count, urinalysis) may be done while you are being treated with Doxazosin.
What lifestyle changes can I make to improve my blood pressure?
Regular exercise and eating a healthy diet will help control your blood pressure and improve your overall health. Engage in physical activity like walking for at least 30 to 60 minutes on most days of the week. If you have not exercised for a long time, start with light exercises such as slow walks. Speak to your doctor about what type of exercise would be suitable for you. Follow a healthy diet plan by eating more fruits, vegetables, whole grains and low-fat dairy products and reduce your intake of foods high in saturated fat, cholesterol and sodium. Cutting down on deep-fried foods and using less salt when cooking can kick-start your healthy diet.
If you smoke, you should try to quit. Smoking is harmful to your blood pressure, heart and overall health. Speak to your doctor or pharmacist about ways to stop your smoking habit.
Doxazosin may cause drowsiness, dizziness, or weakness. If affected, do not drive or take part in any activity in which you need to be alert.
You may experience dizziness when getting up from a sitting or lying down position, especially if you are taking this medicine for the first time. This is common and should disappear gradually as you get used to Doxazosin. It will help if you get up slowly from a sitting or lying position.
Other side effects may include any of the following: headache, nausea, dry mouth, stomach pain, indigestion, weakness, cough, colds, difficulty sleeping, muscle or joint pain, and swelling of the ankles, feet, or hands.
Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
- chest pain, fast and irregular heartbeat
- lightheadedness or fainting
- prolonged and painful penile erection
- rashes, breathlessness, swelling of the face, eyes, or mouth
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking any of these medicines:
- other medicines for high blood pressure
- medicines for sexual dysfunction e.g. sildenafil, tadalafil, vardenafil
- medicines to treat fungal infection e.g. ketoconazole, itraconazole, voriconazole
- certain antibiotics e.g. telithromycin, clarithromycin
- medicines for HIV infection e.g. indinavir, ritonavir, saquinavir
This list does not include all medicines that may interact with Doxazosin.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements, and medicines that you buy without a prescription.
Avoid alcohol.
Cut down on your salt intake. This may help lower your blood pressure and improve your overall health. Discuss with your doctor or dietitian about ways to cut down on your salt intake.
Store in a cool, dry place away from the reach of children.
Medicines must not be used past the expiry date.
Sign Out
