The prostate is a small male organ weighing approximately 15 to 20 g located inferior to the bladder and surrounds the urethra. It produces fluid which contributes to ejaculate volume, but may also prevent infectious processes as this fluid has concentrated quantities of zinc.1 As men age, the prostate—under the influence of androgenic hormones—may begin to grow which increases risk for benign prostatic hyperplasia (BPH). BPH is the most common urological condition in aging men with histological evidence of its presence approaching 90% in octogenarians.2,3 Patients with BPH often have increased smooth muscle tissue in the prostate containing α1-adrenergic receptors resulting in vasoconstriction and subsequent narrowing of the urethral lumen. Patients may also have symptoms of physical obstruction, resulting from an enlarged prostate.
Lower urinary tract symptoms (LUTS) suggestive of BPH are characterized as those associated with impaired bladder emptying or storage.4 Voiding symptoms are often found early in the disease course and include urinary hesitancy, weak urinary stream, and the sensation of incomplete bladder emptying. Storage symptoms include urinary frequency, nocturia, urinary urgency, and urge incontinence. These symptoms occur after several years of untreated BPH as the bladder smooth muscle hypertrophies and weakens.5 BPH can increase the risk of urinary tract infections, bladder stones secondary to urinary stasis, and renal impairment, thus adversely affecting quality of life.6 The most serious complication of BPH is acute urinary retention, which often requires immediate catheterization.
Patients with LUTS should be referred to their physician as a detailed history and physical examination are necessary to exclude other possible etiologies, including other genitourinary tract disorders such as prostate cancer or urinary tract infections, neurological or endocrine disorders. A digital rectal examination (DRE) is necessary to determine prostate size and whether any nodules suggestive of malignancy are present.7 A urinalysis may also be done to exclude urinary tract infections or bladder stones. Pharmacists should be aware of several medication classes for potentially worsening LUTS, including medications with anticholinergic properties such as antihistamines, tricyclic antidepressants, and opiates. Furthermore, as prostate tissue contains α1-adrenergic receptors, α-agonists such as pseudoephedrine or other decongestants may exacerbate symptoms or attenuate therapy with α1-adrenergic antagonists.
Appropriate treatment depends on multiple factors: LUTS severity, concurrent medical illness that affects hemodynamic stability, prostate size, and presence of BPH-related complications. The American Urological Association (AUA) has developed a scoring system to rate symptoms of BPH.7 Patients with mild BPH (AUA score of 0-7) may be candidates for watchful waiting if symptoms are not bothersome. This is a reasonable strategy as symptoms of BPH often wax and wane and therefore active treatment may not always be needed.8 If this strategy is used, patients should be monitored for any potential worsening of symptoms indicating the need for pharmacologic treatment.
For patients with moderate to severe BPH (AUA score 8-35), α1-adrenergic antagonists are effective in ...