Flomax Long-Term Side Effects

Flomax, or tamsulosin, is a prescribed medication used to treat the signs and symptoms of benign enlargement of the prostate gland, or benign prostatic hypertrophy (BPH), according to MayoClinic.com 12. Prostate enlargement is common in older men and can make urinating difficult. Specifically, an enlarged prostate causes a weak urine stream and incomplete bladder emptying. Flomax relaxes the muscles in the prostrate gland, which prevents it from impinging on the urinary tract. Although beneficial, a patient taking Flomax should be aware of the long-term side effects.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.


According to Drugs.com, headache is associated with long-term use of Flomax in some patients 12. Specifically, 21 percent of men taking 0.8 mg of Flomax for a 13-week period experienced headache. This occurs because the chemicals in Flomax may affect the blood vessels in the brain or other brain tissue that can cause a long-term headache. In this case, a patient should let his doctor know that he is experiencing a headache before he attempts self-treatment with over-the-counter (OTC) medications. The doctor may adjust the dosage of Flomax, or prescribe a different medication that does not cause headache.

Abnormal Ejaculation

Men taking Flomax may experience abnormal ejaculation over the long-term, states Drugs.com 12. A 13-week study showed that 18 percent of men taking Flomax experience ejaculation problems. This occurs because Flomax primarily affects the muscles in the prostate gland, which is a gland that contributes to the ejaculation fluids. A man experiencing ejaculation difficulties should schedule an appointment with his doctor for proper assessment and treatment of abnormal ejaculation. The doctor may prescribe a different medication that does not cause ejaculation problems.


Flomax may cause dizziness in some men, states Drugs.com 12. In a 13-week trial, 17 percent of men experienced frequent dizziness when taking Flomax. This occurs because the chemicals in Flomax may cause adverse affects on the brain, which can lead to dizziness. Dizziness may make it difficult for a patient to complete activities of daily living. In addition, dizziness may cause difficulty with driving or with operating other heavy machinery. A man experiencing dizziness should let his doctor know that this long-term side effect is not improving. The doctor will make sure that dizziness is a side effect of Flomax and treat accordingly.