Benign Prostatic Hyperplasia
Tamsulosin is used to reduce urinary obstruction and relieve associated manifestations in hypertensive or normotensive patients with symptomatic benign prostatic hyperplasia (BPH, benign prostatic hypertrophy). Tamsulosin relieves mild to moderate obstructive manifestations (e.g., hesitancy, terminal dribbling of urine, interrupted or weak stream, impaired size and force of stream, sensation of incomplete bladder emptying or straining) and improves urinary flow rates in a substantial proportion of patients and may be a useful alternative to surgery, particularly in those who are awaiting or are unwilling to undergo surgical correction of the hyperplasia (e.g., via transurethral resection of the prostate [TURP]) or who are not candidates for such surgery. Therapy with α1-adrenergic blocking agents appears to be less effective in relieving irritative (e.g., nocturia, daytime frequency, urgency, dysuria) than obstructive symptomatology, although tamsulosin also has been shown to be effective in relieving irritative symptoms. In addition, therapy with α1-adrenergic blocking agents generally can be expected to produce less subjective and objective improvement than prostatectomy, and periodic monitoring (e.g., performance of digital rectal examinations, serum creatinine determinations, serum prostate specific antigen [PSA] assays) is indicated in these patients to detect and manage other potential complications of or conditions associated with BPH (e.g., obstructive uropathy, prostatic carcinoma).
Results of several controlled studies indicate that tamsulosin is more effective than placebo and limited data suggest that the drug is at least as effective as other α1-adrenergic blocking agents (e.g., doxazosin, prazosin, terazosin) in the management of BPH. While symptomatic improvement has been maintained for up to at least 60 weeks of tamsulosin therapy in some patients, the long-term effects of α-blockers on the need for surgery and on the frequency of developing BPH-associated complications such as acute urinary obstruction remain to be established. Although tamsulosin appears to be associated with a decreased incidence of adverse cardiovascular effects including hypotension, dizziness, and syncope, patients should be warned of the possibility of tamsulosin-induced postural dizziness and measures to take if it develops (e.g., sitting, lying down). During initiation of tamsulosin therapy, patients should be cautioned to avoid situations where injury could result if syncope occurs. If syncope occurs, the patient should be placed in a recumbent position and treated supportively as necessary.
Combination therapy with an α1-blocker and 5α-reductase inhibitor (e.g., finasteride) has been more effective than therapy with either drug alone in preventing long-term BPH symptom progression; combined therapy also can reduce the risks of long-term acute urinary retention and the need for invasive therapy compared with α-blocker monotherapy.
For additional information on the use of α1-blockers in the management of BPH,
Allergic-type reactions, including skin rash, pruritus, urticaria, and angioedema of the tongue, lips, and face, have been reported in some patients with positive rechallenge of tamsulosin therapy.
The possibility of carcinoma of the prostate and other conditions associated with manifestations that mimic those of BPH should be excluded in any patient for whom tamsulosin therapy for presumed BPH is being considered.
The manufacturer states that tamsulosin should not be used in the management of hypertension.