Generic Name: tamsulosin
Flomax is used in the treatment of benign prostatic hyperplasia; overactive bladder; urinary tract stones and belongs to the drug class antiadrenergic agents, peripherally acting. There is no proven risk in humans during pregnancy.
FlomaxAll medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Flomax:
Back pain; cough; decreased sexual ability; diarrhea; dizziness; drowsiness; headache; light-headedness; runny or stuffy nose; sinus inflammation; trouble sleeping; weakness.Seek medical attention right away if any of these SEVERE side effects occur when using Flomax:
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, throat, or tongue; unusual hoarseness); blurred vision; chest pain; fainting; fast or irregular heartbeat; fever, chills, or persistent sore throat; prolonged, painful erection; red, swollen, blistered, or peeling skin; severe of persistent dizziness or light-headedness; shortness of breath.This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
Side Effects by Body System - for Healthcare Professionals
Nervous systemIn one case report, seizure frequency increased in a patient with medial temporal lobe seizures following initiation of tamsulosin treatment. Prior to the use of tamsulosin, the patient experienced 3 to 4 seizures per year. In the first 3 months after starting tamsulosin, seizures were appearing twice a month and by the fourth month of treatment the patient had 3 seizures in one day. Following withdrawal of tamsulosin, seizure frequency returned to baseline.
Nervous system side effects are among the most common and include headache in 4% to 20%, asthenia in 1% to 8%, dizziness in 5% to 15%, somnolence in 0% to 4%, and insomnia in 1% to 2% of patients. (These side effects were also noted among patients treated with placebo in controlled trials, but occurred more often among patients treated with tamsulosin.) According to one case report, tamsulosin caused exacerbation of seizures in a patient with a history of seizures.
GenitourinaryAbnormal ejaculation includes ejaculation failure, ejaculation disorder, retrograde ejaculation and ejaculation decrease. In controlled studies, abnormal ejaculation was associated with the use of tamsulosin and was dose-related. The results of one study suggest that intermittent use of tamsulosin may allow for improvement in abnormal ejaculation.
Genitourinary complaints include abnormal (retrograde or decreased volume) ejaculation among 8% (0.4 mg) to 18% (0.8 mg) of male patients. The occurrence of abnormal ejaculation among males who were given placebo in controlled trials averaged 0.2%. Other genitourinary side effects have included impotence (2.9%) and rare cases of urinary retention and priapism.
RespiratoryRespiratory system side effects include rhinitis in 1% to 18%, pharyngitis in 5%, increased cough in 4%, and sinusitis in 3% of patients. In controlled studies, these side effects were also noted in similar but slightly lower incidences among patients who were treated with placebo.
MusculoskeletalMusculoskeletal complaints--back or chest pains--were reported among 4% to 8% of patients in controlled trials, compared with 4% to 7% among patients who were treated with placebo.
CardiovascularRarely, flushing and tachycardia have been associated with the use of tamsulosin.
Cardiovascular side effects including rare occurrences of orthostatic hypotension have been reported. In two US studies, symptomatic postural hypotension was reported by 0.2% (0.4 mg), 0.4% (0.8 mg), and 0% (placebo) of patients. Syncope was reported by 0.2%, 0.4%, and 0.6% of patients in the above groups, respectively. Because of the risk of syncope, it is recommended that patients be warned against situations where injury could result were syncope to occur.
GastrointestinalGastrointestinal side effects include diarrhea in 5% and nausea in 3% of patients. In controlled studies, these side effects were also noted in similar but slightly lower incidences among patients who were treated with placebo. Rarely, constipation, gastric pain, dysphagia, and anorexia have been associated with the use of tamsulosin.
OcularAlthough the overall prevalence of intraoperative floppy iris syndrome (IFIS) is 1% to 2%, the incidence of IFIS associated with the use of tamsulosin ranges from 43% to 63%. Most reports were in patients treated with an alpha-1 blocker at the time IFIS occurred, but in some instances the alpha-1 blocker had been stopped prior to surgery. The manufacturer recommends that male patients be questioned to determine whether or not they have taken tamsulosin or other alpha-1 blockers prior to being considered for cataract surgery. If it is determined that the patient has taken an alpha-rt1 blocker, the patient's ophthalmologist should be prepared for possible modifications to their surgical technique that may be necessary should IFIS be observed during the procedure.
Clinical studies in men 66 years of age and older who were exposed to tamsulosin within 14 days of cataract surgery was significantly associated with serious postoperative ophthalmic adverse events other than IFIS.
Ocular side effects including amblyopia have been reported in 0.2% of men given 0.4 mg, 2% of men given 0.8 mg, and in 0.4% of men who were given placebo.
Intraoperative Floppy Iris Syndrome (IFIS) has been observed in some patients undergoing phacoemulsification cataract surgery while being treated with alpha-1 blockers including tamsulosin.