Get emergency medical help if you have signs of an allergic reaction ro Flomax: 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.
Common Flomax side effects may include:
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.
This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.
 Flomax side effects (more detail)
