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Flomax® (tamsulosin HCI) Capsules: Questions & Answers

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What is Flomax used for?

Flomax is used for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH). Flomax is not used for the treatment of hypertension.


How does Flomax help treat BPH?

Flomax is in a class of medicines called alpha1a-adrenergic antagonists. Flomax capsules relax the smooth muscles in the prostate and the opening of the bladder at the site of obstruction, resulting in improved urine flow and reduced BPH symptoms. Flomax however will not shrink the prostate. The prostate may continue to get larger. This may cause the symptoms to become worse over time. Therefore, even though Flomax may lessen the problems caused by enlarged prostate now, surgery may still be needed in the future.


How should I take Flomax?

The recommended dose of Flomax for treatment of the signs and symptoms of BPH is 0.4 mg once daily. The dose should be taken one-half hour after the same meal each day. For example, if you take Flomax with your evening meal, it should be taken every day 30 minutes after you finish your evening meal. Try to keep your meal times consistent.


What are the side effects of Flomax?

Flomax is generally well tolerated. Compared to placebo, the most common side effects in short-term trials are: asthenia, abnormal ejaculation, infection, dizziness, and rhinitis.


Orthostatic hypotension is a sudden drop in blood pressure that can occur with the first dose of Flomax or when changing doses of Flomax. Such a drop in blood pressure, although rare, may be associated with fainting, dizziness, or lightheadedness. You should get up slowly from a chair or bed, until you know how you will react to Flomax.


Although these symptoms are uncommon, you should not drive or do any hazardous tasks until you are used to the side effects of Flomax for at least 12 hours after the first dose of Flomax. One way to avoid this may be to take your first dose in the evening when you are not planning on leaving the house. After the first dose or two, you will know how Flomax affects you.


If you begin to feel dizzy, sit down until you feel better. If you stop your treatment or forget to take it for several days or more, restart Flomax only after talking with your doctor. If you experience any other side effect, such as prolonged, painful erection of the penis, which is unrelieved by sexual intercourse or masturbation, please contact our doctor immediately.


Who should not take Flomax?

Flomax should not be taken by anyone who has a known allergy to tamsulosin HCl or any component of Flomax capsules.


Can I take Flomax with my other medicines?

When taking any new medicine, it is important to tell your doctor all the medicines you are currently on to make sure there are no harmful interactions between them. When you are taking Flomax, it is especially important that your doctor know if you are taking any of the following:

•  Blood pressure medicine - the effects of blood pressure medicines may increase when taken with

   Flomax. The chance of orthostatic hypotension may increase as well.

•  Coumadin® (warfarin) and Flomax should be used together with caution.


What if I miss a dose?

If you miss a dose of this medicine, skip the missed dose and go back to your regular dosing schedule. Do not double doses.



Flomax® package insert. Ridgefield, CT: Boehringer Ingelheim Pharmacetuicals, Inc.; 2002 Aug.


Lee M. Management of Benign Prostatic Hyperplasia. In: Pharmacotherapy; A pathophysiologic approach. 5th ed. Dipiro JT, Talbert RL, Yee GC, et al., eds. New York: McGraw-Hill; 2002:1533-42.


Coumadin is a registered trademark of Bristol-Myers Squibb Company.

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