Indications 

Flomax is a prescription medication utilized to alleviate the symptoms associated with benign prostatic hyperplasia (BPH), bladder outlet obstruction, and kidney stones. It can be used either alone or in combination with other medications. Flomax is classified as an Alpha 1 Blocker. 

Flomax works by blocking alpha-adrenergic receptors in the smooth muscle of the bladder neck and prostate, causing relaxation of these muscles.  

This relaxation improves urine flow and reduces symptoms associated with benign prostatic hyperplasia (BPH) such as difficulty in initiating urination, weak urine flow, and frequent urination, including at night. Flomax does not shrink the size of the prostate. 

Uses and Dosage 

To ensure the best results, take Flomax exactly as prescribed by your doctor, and follow all directions on the prescription label.  

Flomax should be taken once a day, approximately 30 minutes after a meal, at the same time each day. The capsule should be swallowed whole and not crushed, chewed, or opened.  

Flomax may lower blood pressure and cause dizziness or fainting, especially when you first start taking it, or when you start taking it again. Patients should inform their doctor of any prolonged illness that causes diarrhea or vomiting, as this can cause blood pressure to get too low.  

Blood pressure will need to be checked regularly and patients should be screened for prostate cancer before and during treatment with Flomax. If patients stop taking Flomax for any reason, they should contact their doctor before restarting and may need a dose adjustment.  

Patients should store Flomax at room temperature, away from moisture and heat. All patient information, medication guides, and instruction sheets should be read carefully and any questions should be directed to the doctor or pharmacist. 

Side Effects 

Allergic Reactions 

• Hives, rash, itching 
• Difficulty breathing 
• Swelling of face, lips, tongue, or throat 

Stop using Flomax and call your doctor immediately if you experience: 

• Light-headed feeling, like you might pass out 
• Painful or prolonged (4+ hours) penis erection 
• Severe skin reaction, including fever, sore throat, skin pain, red or purple skin rash that spreads and causes blistering and peeling 

Common Side Effects 

• Dizziness, drowsiness, weakness 
• Nausea, diarrhea 
• Headache, chest pain 
• Abnormal ejaculation, decreased amount of semen 
• Back pain, blurred vision, tooth problems 
• Fever, chills, body aches, flu symptoms 
• Runny or stuffy nose, sinus pain, sore throat, cough 
• Sleep problems (insomnia) 
• Decreased interest in sex 

Note that this is not a complete list of all possible side effects, and patients should consult with their doctor if they experience any other side effects while taking Flomax. 

Caution 

Patients with a known allergy to tamsulosin should avoid using Flomax, and should not take tamsulosin with other drugs in the same class, such as alfuzosin, doxazosin, prazosin, silodosin, or terazosin. 

Flomax use may result in dizziness or fainting, particularly during initial treatment or following treatment interruption. Caution should be exercised when performing tasks requiring alertness, and standing for extended periods or becoming overheated should be avoided. Rapidly rising from a seated or prone position may cause dizziness. 

If Flomax use is interrupted for any reason, patients should consult their physician prior to resuming treatment, as a dosage adjustment may be necessary. 

Tamsulosin has the potential to affect pupil size during cataract surgery. Patients should inform their eye surgeon in advance of using Flomax, and not discontinue medication prior to surgery unless instructed to do so by the surgeon. 

Numerous other drugs have the potential to interact with tamsulosin, and patients should inform their physician of all medications they are taking. 

Patients should carefully adhere to all instructions on their medication label and package, and communicate all medical conditions, allergies, and medications with each of their healthcare providers.