Terazosin for benign prostatic hyperplasia

Lower urinary tract symptoms associated with benign prostatic obstruction (BPO) occur in up to 70% of men over the age of 60 years. To relieve these bothersome symptoms, treatment options include alpha-antagonists, also know as alpha-blockers.

We conducted a systematic review to evaluate the effectiveness and adverse effects of the alpha-blocker, terazosin, for treatment of urinary symptoms associated with BPO.

Trials were searched in computerized general and specialized databases (MEDLINE, Cochrane Library), by checking bibliographies, and by contacting manufacturers and researchers.

Studies were included if they (1) were randomized trials of at least 1 month duration, and (2) included men with symptomatic BPO and compared terazosin with placebo or active controls.

Study, patient characteristics and outcomes data were extracted in duplicate onto standardized forms utilizing a prospectively developed protocol. The main outcome measure for comparing the effectiveness of terazosin with placebo or other BPO medications was change in urological symptoms as measured by validated symptom scores. Secondary outcomes included urodynamic measures. The main outcome measure for adverse effects was the number of men reporting side effects. We also evaluated the number of men withdrawing from treatment and the number withdrawing due to adverse effects.

17 studies involving 5,151 subjects met inclusion criteria (placebo-controlled (10); alpha-blockers (7); finasteride alone or in combination with terazosin as well as placebo (1); microwave therapy (TUMT) (1). Study duration ranged from 4-52 weeks. Mean age was 65 years and 82% of men were white. Baseline urologic symptom scale scores and flow rates demonstrated that men had moderate BPO. Efficacy outcomes were rarely reported in a fashion that allowed for data pooling but indicated that terazosin improved symptom scores and flow rates more than placebo or finasteride and similarly to other alpha antagonists. The pooled mean percentage improvements for the Boyarsky symptom score was 37% for terazosin versus 15% for placebo (n=4 studies). The mean percentage improvement for the American Urological Association symptom score (AUA) was 38% compared to 17% and 20% for placebo and finasteride, respectively (n = 2 studies). The pooled mean improvement in the International Prostate Symptom Score (IPSS) (40%) was similar to tamsulosin (43%). Peak urine flow rates improved greater with terazosin (22%), than placebo (11%) and finasteride (15%) but did not differ significantly from the other alpha-blockers. The percentage of men discontinuing terazosin was comparable to men receiving placebo and finasteride but was greater then with other alpha-antagonists. Adverse effects were greater than placebo and included dizziness, asthenia, headache and postural hypotension.

The available evidence suggests that terazosin improves urinary symptoms and flow measures associated with BPO. Effectiveness is superior to placebo or finasteride, similar to other alpha-blockers but less than TUMT. Adverse effects were generally mild but more frequent than other alpha-blockers and associated with between a two-four fold increase in treatment discontinuation.