Trade Names:Flomax- Capsules 0.4 mgNovo-Tamsulosin (Canada)Sandoz Tamsulosin (Canada)
Selectively blocks alpha 1 -adrenergic receptors causing relaxation of prostate smooth muscle resulting in an increase in urinary flow rate and a reduction in symptoms of benign prostatic hypertrophy.
Tamsulosin absorption is greater than 90% (fasting), and T max is 4 to 5 h (fasting) and 6 to 7 h (with food). Taking tamsulosin under fasted conditions results in a 30% increase in bioavailability (AUC) and 40% to 70% increase in peak concentrations.
Steady state is achieved by the fifth day of every day dosing. Vd is about 16 L. Tamsulosin is widely distributed to most tissues, including kidney, prostate, liver, gall bladder, heart, aorta, and brown fat. There is minimal distribution to brain, spinal cord, and testes. The drug is 94% to 99% protein bound.
Tamsulosin is extensively metabolized by CYP-450 in the liver.
Tamsulosin t ½ is 5 to 7 h. Approximately 10% is excreted unchanged in urine.
AUC is 40% higher in subjects 55 to 75 yr of age compared with subjects 20 to 32 yr of age.
Treatment of signs and symptoms of benign prostatic hyperplasia.
PO 0.4 mg/day, administered approximately 30 min following the same meal each day. If the patient fails to respond after 2 to 4 wk, the dose may be increased to 0.8 mg/day.
Store at controlled room temperature (59° to 86°F). Protect from excessive moisture.
Concomitant use may decrease tamsulosin Cl and increase the AUC. Use with caution.
None well documented.
Headache (21%); dizziness (17%); somnolence (4%); decreased libido (2%); insomnia (1%).
Rhinitis (18%); pharyngitis (5%); amblyopia (2%).
Diarrhea (6%); nausea (4%); tooth disorder (2%).
Abnormal ejaculation (18%).
Increased cough (5%); sinusitis (4%).
Infection (11%); asthenia (9%); back pain (8%); chest pain (4%).
Category B .
Not indicated for use in women.
Safety and efficacy not established.
Tamsulosin is currently not indicated for the treatment of hypertension.
Association is rare; can lead to permanent impotence if not properly treated.
Rule out before starting therapy.
Hypotension, severe headache.
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