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.

  • What should I know when beginning and continuing on this medication?

    How does this medication work?

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

    What are the beneficial effects of this medication and when should I begin to have results?

    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?

    Your healthcare provider may order tests regularly and ask you questions from time to time to check how well this medication is working.

  • What are the possible side effects of this medication?

    The following is not a full list of side effects. Side effects cannot be anticipated. If any develop or change in intensity, tell your healthcare provider as soon as possible. Only your healthcare provider can determine if it is safe for you to continue taking 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.

  • What should I tell my healthcare provider before I take the first dose of this medication?

    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?

    The information below is based on the dosage guidelines your healthcare provider uses. Depending on your condition and medical history, your healthcare provider may prescribe a different regimen. Do not change the dosage or stop taking your medication without your healthcare provider's approval.

    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.

  • What are the possible food and drug interactions associated with this medication?

    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.

  • May I receive this medication if I am pregnant or breastfeeding?

    Flomax is not for use in women.

  • What should I do if I miss a dose of this medication?

    If you miss a dose of Flomax, take it as soon as you remember. However, if it is almost time for your next dose, skip the one you missed and return to your regular dosing schedule. Do not take two doses at once.

    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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