Flomax Tabs (Tamsulosin)

(℞) Prescription Required

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Flomax Tabs 0.4mg

Product of United Kingdom
Manufactured by: Astellas Pharma Ltd
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Flomax Tabs 0.4mg
Product of United Kingdom
Manufactured by Astellas Pharma Ltd
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Tamsulosin Tabs 0.4mg

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Manufactured by: Sandoz
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Tamsulosin Tabs 0.4mg
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Manufactured by Sandoz
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Flomax Tabs 0.4mg

Product of Canada
Manufactured by: Boehringer Ingelheim
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Flomax Tabs 0.4mg
Product of Canada
Manufactured by Boehringer Ingelheim
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Flomax (Tamsulosin) Dosage and Side Effects

FLOMAX is used to treat symptoms of an enlarged prostate, also known as benign prostatic hypertrophy (BPH).  Although commonly thought of as a medication used to treat enlarged prostate, FLOMAX can also be prescribed for women who have problems with bladder blockages or obstruction to help them urinate more easily. Doctors may also prescribe FLOMAX to help the body clear or pass kidney stones.

Warnings and Precautions

People who have very serious kidney problems should not take FLOMAX. You should also not take FLOMAX if you:

  • Have coronary artery disease (CAD), unless your doctor recommends the drug

  • Have liver disease

  • Are about to have surgery and be given anesthesia

  • Tend to become lightheaded upon standing

  • Suffer from painful erections for unusually long periods of time (priapism)

Additionally, people who take FLOMAX for the first time may feel faint or pass out.

This usually subsides shortly after taking the medication.

Pregnancy and FLOMAX

FLOMAX is generally considered safe to take during pregnancy.

Regardless, you should tell your doctor if you're pregnant or plan to become pregnant before taking this medication.

You should also alert your physician if you're breastfeeding or plan to breastfeed.

It's not recommended that breastfeeding mothers take this medication.

Side Effects

Headache is the most common side effect of taking FLOMAX. Other common side effects include:

  • Dizziness upon standing due to a sudden drop in blood pressure

  • Runny nose

  • Problems with ejaculation

  • Dizziness

  • Joint pain

  • Infection

  • Decreased sex drive

Serious side effects of FLOMAX include:

  • Back pain

  • Sore throat

  • Cough

  • Bitter taste in the mouth

  • An eye condition while undergoing cataract surgery known as floppy iris syndrome

  • Other visual problems

Priapism, a painful and potentially dangerous condition in which an erection lasts for hours, is a rare side effect found in men taking FLOMAX.

The medication may also cause vomiting or constipation.

Interactions with this medication

It's always important to share with your doctor and pharmacist all prescription, non-prescription, illegal, recreational, herbal, nutritional, or dietary drugs you're taking.

You shouldn't take FLOMAX if you're also taking the following drugs:

  • Medications for fungal infections like Sporanox (itraconazole), Noxafil (posaconazole), Vfend (voriconazole), and Nizoral (ketoconazole)

  • HIV/AIDS medications like Kaletra (lopinavir/ritonavir), Norvir (ritonavir), and Stribild (cobicistat/elvitegravir/emtricitabine/tenofovir)

  • Victrelis (Boceprevir)

  • Antibiotics like chloramphenicol, Biaxin (clarithromycin) and Ketek (telithromycin)

  • Vaprisol (conivaptan)

  • Gengraf, Neoral, or Sandimmune (cyclosporine)

  • Rescriptor (delarvirdine), Lexiva (fosamprenavir)

  • Faverin, Fevarin, Floxyfral, Luvox (fluvoxamine)

  • Cancer medications like Gleevec (imatinib)

  • Serzone (nefazodone)

  • Incivek (telaprevir)

You should also avoid taking FLOMAX if you are taking any of the following:

  • Other alpha-blocker medications for prostate conditions like Minipress (prazosin), Rapaflo (silodosin), Hytrin (terazosin)

  • Quinaglute, Quinidec (quinidine)

  • Drugs for depression called selective serotonin reuptake inhibitors (SSRIs) like Zoloft (sertraline) or Prozac (fluoxetine)

  • Drugs for depression called tricyclic antidepressants (TCAs) like Paxil (paroxetine), Anafranil (clomipramine), and Norpramin (desipramine)

  • Antibiotics like Vibramycin (doxycycline); EryTab, E.E.S., or Erythrocin (erythromycin); Vigamox (moxifloxacin)

  • Cocaine

  • Medications for irregular heartbeat like Cordarone, Nexterone, or Pacerone (amiodarone),444 or Multaq (dronedarone)

  • Benadryl (diphenhydramine)

  • Medications for mood like Haldol (haloperidol) or Clozaril (clozapine)

Proper Use of this medication

For enlarged prostate or benign prostatic hypertrophy (BPH): FLOMAX is usually taken once a day in a dose of 0.4 milligrams (mg), 30 minutes after eating.

For best results, try to take FLOMAX at the same time each day.

After your doctor evaluates your condition, he or she may increase the dose of your FLOMAX up to 0.8 mg per day.

For kidney stones: A doctor will typically prescribe 0.4 mg of FLOMAX to be taken once a day.

Once you've passed the kidney stones, your doctor may tell you to continue taking the FLOMAX for another week or two.

Bladder obstruction: Women who take FLOMAX to help relieve symptoms of bladder obstruction are normally prescribed doses of 0.4 mg daily.

FLOMAX Overdose

If you suspect an overdose, contact a poison control center or emergency room immediately.

Missed Dose of FLOMAX

If you miss a dose of FLOMAX, try to take it as soon as you remember as long as it's not too close to bedtime or to the usual time of taking your next dose.

However, if it's almost time for the next dose, skip the missed dose and resume your regular dosing schedule. Don't double up to make up for a missed dose.

If you've missed a few doses of FLOMAX and normally take 0.8 mg a day, your doctor may need to lower your dose.

Other related products

The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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