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URL of this page: https://medlineplus.gov/druginfo/meds/a698012.html

Tamsulosin

pronounced as (tam soo' loe sin)

Why is this medication prescribed?

Tamsulosin is used in men to treat the symptoms of an enlarged prostate (benign prostatic hyperplasia or BPH) which include difficulty urinating (hesitation, dribbling, weak stream, and incomplete bladder emptying), painful urination, and urinary frequency and urgency. Tamsulosin is in a class of medications called alpha blockers. It works by relaxing the muscles in the prostate and bladder so that urine can flow easily.

How should this medicine be used?

Tamsulosin comes as a capsule to take by mouth. It is usually taken once a day. Take tamsulosin 30 minutes after the same meal each day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take tamsulosin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow tamsulosin capsules whole; do not split, chew, crush, or open them.

Your doctor will probably start you on a low dose of tamsulosin and may increase your dose after 2 to 4 weeks.

Tamsulosin may help control your condition, but it will not cure it. Continue to take tamsulosin even if you feel well. Do not stop taking tamsulosin without talking to your doctor.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking tamsulosin,

  • tell your doctor and pharmacist if you are allergic to tamsulosin, sulfa medications, or any other medications.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements and herbal products you are taking or plan to take. Be sure to mention any of the following: other alpha blocker medications such as alfuzosin (Uroxatral), doxazosin (Cardura), prazosin (Minipress), and terazosin (Hytrin); anticoagulants ('blood thinners') such as warfarin (Coumadin); cimetidine (Tagamet); and medications for erectile dysfunction (ED) such as sildenafil (Viagra), tadalafil (Cialis), or vardenafil (Levitra); Your doctor may need to change the doses of your medications or monitor you more carefully for side effects.
  • tell your doctor if you have or have ever had prostate cancer or liver or kidney disease.
  • you should know that tamsulosin is only for use in men. Women should not take tamsulosin, especially if they are pregnant or could become pregnant or are breast-feeding. If a pregnant woman takes tamsulosin, she should call her doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking tamsulosin. If you need to have eye surgery at any time during or after your treatment, be sure to tell your doctor that you are taking or have taken tamsulosin.
  • you should know that this medication may make you drowsy or dizzy. Do not drive a car, operate machinery, or perform dangerous tasks until you know how this medication affects you.
  • you should know that tamsulosin may cause dizziness, lightheadedness, a spinning sensation, and fainting, especially when you get up too quickly from a lying position. This is more common when you first start taking tamsulosin or after your dose is increased. To help avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up. Call your doctor if these symptoms are severe or do not go away.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one. If you interrupt your treatment for several days or longer, call your doctor before restarting the medication, especially if you take more than one capsule of tamsulosin a day.

What side effects can this medication cause?

Tamsulosin may cause side effects. Tell your doctor if any of these symptoms or those in the SPECIAL PRECAUTIONS section are severe or do not go away:

  • sleepiness
  • difficulty falling asleep or staying asleep
  • weakness
  • back pain
  • diarrhea
  • runny or stuffy nose
  • pain or pressure in the face
  • sore throat, cough, fever, chills, or other signs of infection
  • blurred vision
  • difficulty ejaculating

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately:

  • painful erection of the penis that lasts for hours
  • rash
  • itching
  • hives
  • swelling of the eyes, face, tongue, lips, throat, arms, hands, feet, ankles, or lower legs

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

  • dizziness
  • fainting
  • blurred vision
  • upset stomach
  • headache

What other information should I know?

Keep all appointments with your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Flomax®

Brand names of combination products

  • Jalyn® (containing Dutasteride, Tamsulosin)
Last Revised - 01/15/2018