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Generic name: tamsulosin (pronounced tam-soo’LOE-sin [tam-soo-LOE-sin])
Drug class: alpha-adrenoreceptor antagonists

What is Flomax?

Flomax (tamsulosin) is part of a class of medicines known as alpha blockers. It relaxes muscles in the bladder and prostate to allow urine to flow freely. Flomax capsules are prescribed to men to treat symptoms of an increased prostate (benign prostatic hyperplasia, or BPH) that include problems with urination (hesitation or dribbling stream and insufficient bladder emptying), painless urination, and urgency and frequency of urination. Flomax capsules aren't approved for use by children or women.


It is not recommended to use Flomax if you are allergic to tamsulosin. Do not use tamsulosin together with similar medications like alfuzosin (Uroxatral), doxazosin (Cardura), prazosin (Minipress), silodosin (Rapaflo), and terazosin (Hytrin). Flomax could cause dizziness and fainting, particularly at the beginning of your first time taking it or when you begin taking it again. Be aware when you drive or engage in any activity that requires you to be alert. Avoid standing for extended durations or becoming hot during exercise or in hot temperatures. Do not get up too fast from a lying or sitting position. You may get dizzy.

If you decide to stop taking this medicine for any reason, contact your doctor prior to starting the process again. It could be necessary to make an adjustment. Tamsulosin can affect your pupils during cataract surgery. Be sure to inform your eye doctor prior to surgery that you're taking this drug. Don't stop taking Flomax prior to surgery unless your doctor instructs you to. There are a variety of other medications that may interfere with this medication. Inform your doctor about any medications you take.

Follow the instructions on your prescription label and on the label of your package. Be sure to inform your health care providers about your medical ailments and allergies, as well as the medicines you are taking.

Before you take this drug 

It is best not to take Flomax if you are allergic to tamsulosin.

To ensure that this medication is suitable for you, inform your doctor if you've previously had:

  • Prostate cancer;

  • Lower blood pressure;

  • An allergic reaction to the sulfa-containing drugs an allergy to sulfa drugs

  • Kidney or liver disease.

Tamsulosin may affect your eyes. If you're having cataract surgery, inform the doctor that you are using this medication.

Consult your physician about screening for prostate


prior to and while taking this medication.

Flomax capsules aren't authorised for use by women. 

How to take Flomax?

Use Flomax tablets exactly as directed by your physician. Follow all instructions on the prescription label, and review all medication guides and instructions.

Flomax capsules are generally consumed once per day for 30 minutes following the same meal on a daily basis. Take the capsule in its entirety and don't crush or chew on it, break it, or even open it. Your blood pressure is likely to be checked regularly.

If you decide to stop taking this medication, you should not restart it without your physician's guidance. Keep tightly sealed to keep at room temperature and away from heat and humidity.

What happens If I Miss the dose?

Do not take the medicine for as long as you are able, but avoid any missed doses if it's nearing the time to take the next dose. Don't take two doses at once. If you have stopped taking this medication for several consecutive days, do not begin the process again without seeking your physician's guidance.

Detail on dosage 

Usual Adult Dose for Benign Prostatic Hyperplasia:

0.4 mg once per day. The dose can be increased to 0.8 mg once a day for patients who do not react to 0.4 mg once daily within 2 to 4 weeks.


The medication should be administered around half an hour after eating the same meal throughout the day.

Use: benign prostatic hyperplasia (BPH)

What happens If I overdose?

Get medical attention in an emergency or contact the Poison Help line toll-free at 1-800-222-1222.

What should be avoided?

Avoid driving or engaging in hazardous activities until you understand the effects of this medication on your body. Your reaction could be affected. Be careful not to get up too fast from a lying or sitting position, as you could get dizzy.

Side effects of Flomax

See a doctor immediately. If you are experiencing symptoms that you are experiencing an allergic reaction to Flomax (hives, breathing difficulties, and swelling of your throat or face) or an intense skin reaction (fever, throat soreness, burnt eyes, irritation, and an ailment that is purple or red that blisters and peels), Tamsulosin could lower your blood pressure and cause confusion or fainting, particularly when you are first beginning to take it or when the dose you take changes. Tamsulosin may cause serious side effects. Stop taking Flomax and consult your physician immediately if you suffer from:

  • An euphoric feeling, similar to feeling like you're about to pass out or

  • An uncomfortable erection lasting for 4 hours or more.

Common Flomax adverse effects could include:

  • Abnormal ejaculation, less quantity of semen;

  • Dizziness, drowsiness, weakness;

  • Nasal stuffiness or runny nose, sore throat, sore throat,

  • Back pain and ch

    est pain; migraine;

  • Nausea, diarrhoea;

  • Tooth issues;

  • Blurred vision

  • Sleep problems (insomnia); or

  • Less interest in sex.

This is not a comprehensive list of all the side effects. Other side effects could be present. Contact your physician to seek medical advice on the effects. You can report symptoms to the FDA at 1-800-FDA-1088.

Interaction with drugs 

There are times when it's not recommended to take certain medications in conjunction with other medications. Certain medications can alter your blood levels from other medications you take, which could cause more side effects or make the medication less effective.

Inform your doctor about the medicines you are currently taking. Numerous drugs can interact with Tamsulosin's effects, including:

  • Cimetidine;

  • Medicine to treat impotence or pulmonary arterial hypertension—avanafil (Stendra), sildenafil (Viagra, Revatio), tadalafil (Adcirca, Cialis), or vardenafil (Levitra, Staxyn); or

  • Medicines for treating hypertension or prostate problems—alfuzosin and doxazosin, silodosin, prazosin, and terazosin.

This list isn't complete, and there are many other medications that can interfere with tamsulosin. This includes prescription and over-the-counter drugs, vitamins, and herbal products. The interactions of all drugs are included here.



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