Tamsulosin (Flomax) is An Alpha-Blocker that Relaxes the Muscles in the Prostate and Bladder Neck, Making it easier to urinate.

Tamsulosin dosing information

Usual Adult Dose for Benign Prostatic Hyperplasia:

Initial Dose: 0.4 mg orally once a day
Maximum Dose: 0.8 mg orally once a day

Tamsulosin Side Effects :

If you have signs of an allergic reaction to tamsulosin: hives, rash, itching; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using this medicine and call your doctor at once if you have:

A light-headed feeling, like you might pass out;

Penis Erection that is painful or lasts 4 hours or longer; or

severe skin reaction fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

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); or
Decreased Interest in sex