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    DEA Class;  Rx

    Common Brand Names; Flomax

    • Alpha1 Blockers; 
    • BPH, Alpha Blockers

    Oral alpha-blocker; used once-daily for BPH; may cause less hypotension than other alpha-blockers due to specificity for prostate alpha-receptors.

    Indicated for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH).

    For medical expulsive treatment (MET) as an adjunct to conservative management of distal uretal nephrolithiasis.


    • Headache (19-21%)
    • Orthostatic hypotension (6-19%)
    • Rhinitis (13-18%)
    • Abnormal ejaculation (8-18%)
    • Dizziness (15-17%)
    • Arthralgia (11%)
    • Infection (9-11%)
    • Asthenia (8%)
    • Back pain (7-8%)
    • Skin rash (7%)
    • Pharyngitis (5-6%)
    • Diarrhea (4-6%)
    • Myalgia (5%)
    • Chest pain (4%)
    • Cough (3-4%)
    • Somnolence (3-4%)
    • Nausea (2-4%)
    • Sinusitis (2-4%)
    • Abdominal discomfort (2-3%)
    • Bitter taste (2-3%)
    • Decreased libido (1-2%)
    • Insomnia (1-2%)

    Use with caution in coronary artery disease, liver disease, general anesthesia

    Orthostatic hypotension may occur

    Priapism rarely reported

    Prostatic cancer should be ruled out before therapy is initiated

    May cause syncope (first-dose effect)

    Discontinue if angina symptoms occur or worsen

    Intraoperative floppy iris syndrome has been reported in patients receiving alpha1 blockers at time of cataract surgery; association is unclear

    Patients with sulfa allergy have rarely developed allergic reaction; avoid use if previous sulfa allergy reactions have been life-threatening

    Not for use as antihypertensive drug

    May exacerbate heart failure

    No data are available on use in pregnant women

    No adverse developmental effects observed in animal studies administering tamsulosin to rats or rabbits during organogenesis

    There are no data on presence of drug in human milk, effects on breastfed infant, or on milk production

    No data are available; owing to potential of tamsulosin to cause hypotension, breastfeeding is not recommended if taking tamsulosin


    0.8 mg/day PO.


    0.8 mg/day PO.


    Safety and efficacy have not been established.


    Safety and efficacy have not been established.



    • 0.4mg