Tamsulosina: What is it? Uses, Warnings, Function, Side Effects and Period of Action

It is a specific alpha 1 antagonist indicated for the symptomatic treatment of benign prostatic hyperplasia.

The oral capsule is available as a brand-name drug and a generic drug whose brand is Flomax.
It comes only as a capsule that you take orally.

The oral tamsulosin capsule is used to treat the symptoms of benign prostatic hyperplasia (BPH) .

Important Warnings

Orthostasis warning: tamsulosin may cause dizziness or a decrease in blood pressure when you wake up after sitting or lying down.

After taking your first dose or a larger dose, be sure you know how tamsulosin affects you before doing any activity that may cause you harm.

Priapism warning: Rarely, tamsulosin may cause priapism. This is a persistent and painful erection that is not related to sexual activity.

If you have priapism, contact your doctor immediately. If priapism is not treated, it could cause permanent impotence (not being able to have an erection).

Skin reactions warning: Although it is rare, this medication can cause serious skin reactions, including a serious condition called Stevens-Johnson syndrome .

These skin reactions can cause elevated welts, facial swelling, fever and shortness of breath. See a doctor immediately or call 911 if you have signs of a sudden or severe skin reaction after taking this medication.

Warning intraoperative flaccid iris syndrome (IFIS): IFIS is a complication that can occur during surgery for cataracts or glaucoma .

Although it is rare, this problem has been reported with people taking tamsulosin. If you need to undergo cataract or glaucoma surgery, be sure to tell your doctor or surgeon that you are taking tamsulosin.

What is tamsulosin?

Tamsulosin is a prescription medication. It is presented as a capsule that you take orally.

Tamsulosin is available as the brand name drug Flomax. It is also available as a generic medicine.

Generic drugs generally cost less than the brand-name version. In some cases, they may not be available in all strengths or forms such as the brand name drug.

This medicine can be used as part of a combination therapy. That means you may need to take it with other drugs.


Tamsulosin is used to treat the symptoms of benign prostatic hyperplasia . It is a condition that can occur in men. With benign prostatic hyperplasia, the prostate enlarges but is not cancerous.

Symptoms of benign prostatic hyperplasia include difficulty urinating and a frequent or urgent need to urinate that often occurs at night.


Tamsulosin belongs to a class of medications called alpha-adrenergic blockers.

A class of medications is a group of medicines that work in a similar way. These medications are often used to treat similar conditions.

Tamsulosin works by relaxing the muscles of the bladder and prostate. This helps improve the flow of your urine.

Side effects

Oral tamsulosin capsule does not cause drowsiness, but may cause other side effects.

Most common side effects:

The most common side effects that can occur with tamsulosin include:

  • Headache.
  • Dizziness.
  • Runny nose.
  • Diarrhea.
  • Tos.
  • Decrease in semen.
  • Loss of energy or muscle strength.
  • Sore throat or difficulty swallowing
  • Back or chest pain

If these side effects are mild, they can go away in a few days or a couple of weeks. If they are more severe or do not go away, talk to your doctor or pharmacist.

Serious side effects:

Call your doctor immediately if you have serious side effects. If your symptoms seem to be life threatening or if you think you are having a medical emergency.

Serious side effects and their symptoms may include the following:

  • Abnormal ejaculation
  • Priapism (painful and lasting erection).
  • Symptoms similar to the flu.
  • Blurry vision.
  • Low blood pressure when changing positions that make you feel dizzy, weak or dizzy.
  • Allergic reaction, with difficulty breathing, fever, swelling of the throat or tongue, rash, itching or hives.

How long does tamsulosin take to function?

Most people notice symptoms of benign prostatic hyperplasia that begin to improve within a week after taking tamsulosin. This is the time it takes for the drug to accumulate in your body at a level that works.

If you do not find it easier to urinate or have less desire to urinate within 2 weeks after you start using this medication, tell your doctor.

Your doctor may need to change your dose or take another medication.