Generic Name: Tamsulosin

  • What is this medication and its most common uses?

    Flomax is a medicine used to treat signs and symptoms of benign prostatic hyperplasia (BPH), a condition that may be referred to as an enlarged prostate.


    How does this medication work?

    Flomax works by relaxing the muscles in the prostate and bladder, thereby allowing urine to flow easily.


    What: Flomax has been shown to improve symptoms of BPH, such as urinating frequently, strong urges to urinate, waking up to urinate, trouble urinating, incomplete bladder emptying, urinary flow that starts and stops, and a weak stream.

    When: Flomax may start improving your symptoms within one week of starting treatment.

    How do I know it is working?


  • What are the possible side effects of this medication?


    More common side effects may include: headache, dizziness, stuffy and runny nose, infection, sexual problems, weakness, back pain, diarrhea, sore throat, chest pain, increased cough, drowsiness, nausea, sinus congestion and pain, trouble sleeping, tooth disorder, blurred vision.

    Less common side effects may include:

    Sudden drop in blood pressure upon standing, especially after the first dose or when changing doses, with symptoms such as fainting, dizziness, or lightheadedness.

    Serious allergic reactions, such as rash, itching, hives, difficulty breathing, blistering of your skin, or swelling of your face, tongue, or throat.

    A painful erection that will not go away, and cannot be relieved by having sex.

    Flomax may also cause eye problems during cataract surgery.

  • Who should not take this medication?

    Do not take Flomax if you are allergic to it or any of its ingredients.

    Flomax should not be used by women.


    Tell your healthcare provider about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Flomax. Also, talk to your healthcare provider about your complete medical history, especially if you have kidney or liver problems, a history of low blood pressure, plan to have cataract surgery, or are allergic to sulfa medications (such as sulfamethoxazole or sulfisoxazole).

  • What is the usual dosage?


    Adults: The recommended dose is 0.4 milligrams once a day. Your healthcare provider may increase your dose as needed.

  • How should I take this medication?

    Take Flomax exactly as prescribed by your healthcare provider. Do not change your dose or stop taking Flomax without first talking to your healthcare provider.

    Take Flomax about 30 minutes after the same meal each day.

    Swallow Flomax capsules whole. Do not crush, chew, or open them.

  • What should I avoid while taking this medication?

    Do not drive, operate machinery, or engage in other dangerous activities until you know how Flomax affects you.


    If Flomax is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your healthcare provider before combining Flomax with the following: cimetidine, erythromycin, ketoconazole, medications for erectile dysfunction (such as sildenafil or tadalafil), paroxetine, terbinafine, or warfarin.


    Flomax is not for use in women.



    If you stop or forget to take Flomax for several days, talk to your healthcare provider before starting again.

  • How should I store this medication?

    Store at room temperature.

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