Brand Names: Flomax
Generic Name: tamsulosin
- What is tamsulosin (Flomax)?
- What are the possible side effects of tamsulosin (Flomax)?
- What is the most important information I should know about tamsulosin (Flomax)?
- What should I discuss with my healthcare provider before taking tamsulosin (Flomax)?
- How should I take tamsulosin (Flomax)?
- What happens if I miss a dose (Flomax)?
- What happens if I overdose (Flomax)?
- What should I avoid while taking tamsulosin (Flomax)?
- What other drugs will affect tamsulosin (Flomax)?
- Where can I get more information (Flomax)?
What is tamsulosin (Flomax)?
Tamsulosin is an alpha-blocker that is used to improve urination in men with benign prostatic hyperplasia (enlarged prostate).
Tamsulosin is not approved for use in women or children.
Tamsulosin may also be used for purposes not listed in this medication guide.
What are the possible side effects of tamsulosin (Flomax)?
Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).
Stop using tamsulosin and call your doctor at once if you have:
- a light-headed feeling, like you might pass out; or
- penis erection that is painful or lasts 4 hours or longer.
Tamsulosin lowers blood pressure and may cause dizziness or fainting, especially when you first start taking it. You may feel very dizzy when you first wake up. Avoid getting up too fast from a sitting or lying position, or you may feel dizzy.
Common side effects may include:
- abnormal ejaculation, decreased amount of semen;
- dizziness, drowsiness, weakness;
- runny nose, cough;
- back pain, chest pain;
- nausea, diarrhea;
- tooth problems;
- blurred vision;
- sleep problems (insomnia); or
- decreased interest in sex.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What is the most important information I should know about tamsulosin (Flomax)?
Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.
What should I discuss with my healthcare provider before taking tamsulosin (Flomax)?
You should not use tamsulosin if you are allergic to it.
Tell your doctor if you have ever had:
- liver or kidney disease;
- prostate cancer;
- low blood pressure; or
- an allergy to sulfa drugs.
Tamsulosin can affect your pupils. If you have cataract surgery, tell your surgeon ahead of time that you use this medicine.
Tamsulosin is not for use in women, and the effects of this medicine during pregnancy or in breastfeeding women are unknown.
How should I take tamsulosin (Flomax)?
Your doctor may test your prostate specific antigen (PSA) to check for prostate cancer before you take tamsulosin.
Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.
Tamsulosin is usually taken once a day, approximately 30 minutes after the same meal each day.
Swallow the capsule whole and do not crush, chew, break, or open it.
Your blood pressure will need to be checked often.
Some things can cause your blood pressure to get too low. This includes vomiting, diarrhea, or heavy sweating. Call your doctor if you are sick with vomiting or diarrhea.
Store at room temperature away from moisture and heat.
If you stop taking tamsulosin for any reason, call your doctor before you start taking it again. You may need a dose adjustment.

SLIDESHOW
Signs of Prostate Cancer: Symptoms, PSA Test, Treatments See SlideshowWhat happens if I miss a dose (Flomax)?
Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.
If you miss your doses for several days in a row, talk with your doctor before restarting the medication.
What happens if I overdose (Flomax)?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I avoid while taking tamsulosin (Flomax)?
Avoid driving or hazardous activity until you know how this medicine will affect you. Your reactions could be impaired. Avoid getting up too fast from a sitting or lying position, or you may feel dizzy.
What other drugs will affect tamsulosin (Flomax)?
Tell your doctor about all your current medicines. Many drugs can increase your risk of very low blood pressure while taking tamsulosin, especially:
- medicines similar to tamsulosin (alfuzosin, doxazosin, prazosin, silodosin, or terazosin);
- heart or blood pressure medication; or
- sildenafil (Viagra) and other erectile dysfunction medicines.
This list is not complete and many other drugs may affect tamsulosin. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.
Where can I get more information (Flomax)?
Your pharmacist can provide more information about tamsulosin.
Copyright 1996-2019 Cerner Multum, Inc.
Health Solutions From Our Sponsors