What is this medication?
TAMSULOSIN (tam SOO loe sin) treats the symptoms of an enlarged prostate (benign prostatic hyperplasia). It works by relaxing the muscles in the prostate and bladder, which makes it easier to urinate. It belongs to a group of medications called alpha blockers.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Flomax
What should I tell my care team before I take this medication?
They need to know if you have any of the following conditions:
- Advanced kidney disease
- Advanced liver disease
- Low blood pressure
- Prostate cancer
- An unusual or allergic reaction to tamsulosin, sulfa drugs, other medications, foods, dyes, or preservatives
- Pregnant or trying to get pregnant
How should I use this medication?
Take this medication by mouth about 30 minutes after the same meal every day. Follow the directions on the prescription label. Swallow the capsules whole with a glass of water. Do not crush, chew, or open capsules. Do not take your medication more often than directed. Do not stop taking your medication unless your care team tells you to.
Talk to your care team about the use of this medication in children. Special care may be needed.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses. If you stop taking your medication for several days or more, ask your care team what dose you should start back on.
What may interact with this medication?
- Medications for erectile dysfunction like sildenafil, tadalafil, vardenafil
- Medications for high blood pressure
- Other alpha-blockers like alfuzosin, doxazosin, phentolamine, phenoxybenzamine, prazosin, terazosin
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medication?
Visit your care team for regular check-ups. You will need lab work done before you start this medication and regularly while you are taking it. Check your blood pressure as directed. Ask your care team what your blood pressure should be, and when you should contact him or her.
This medication may make you feel dizzy or lightheaded. This is more likely to happen after the first dose, after an increase in dose, or during hot weather or exercise. Drinking alcohol and taking some medications can make this worse. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medication affects you. Do not sit or stand up quickly. If you begin to feel dizzy, sit down until you feel better. These effects can decrease once your body adjusts to the medication.
Contact your care team right away if you have an erection that lasts longer than 4 hours or if it becomes painful. This may be a sign of a serious problem and must be treated right away to prevent permanent damage.
If you are thinking of having cataract surgery, tell your eye surgeon that you have taken this medication.
What side effects may I notice from receiving this medication?
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
- Low blood pressure—dizziness, feeling faint or lightheaded, blurry vision
- Prolonged or painful erection
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
- Change in sex drive or performance
- Runny or stuffy nose
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medication?
Keep out of the reach of children.
Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Throw away any unused medication after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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