Comparison of prazosin, terazosin and tamsulosin in the treatment of symptomatic benign prostatic hyperplasia: A short‐term open, randomized multicenter study

Abstract

Background: The objective of this open randomized clinical study was to compare the short-term efficacy and safety of three alpha-1 blockers, prazosin, terazosin and tamsulosin, in the treatment of lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). Methods:The study comprised 121 patients with symptomatic BPH who were randomized to receive 0.5 mg of prazosin twice daily, 0.5 mg of terazosin twice daily or 0.1 mg of tamsulosin once daily for the initial 2 weeks. The doses were doubled for the next 2 weeks. The primary variables assessed were a symptom score, changes in maximum and average urinary flow rate (Q max and Q ave ), postvoid resisual urine volume and blood pressure. Results:The percentage changes in the total symptom score from baseline were 38, 39 and 26% at 4 weeks by prazosin, terazosin and tamsulosin, respectively. Terazosin produced significantly higher improvement in four out of nine individual symptoms than tamsulosin (P < 0.05). A significant increase in Q max or Q ave in uroflowmetry was obtained in the prazosin and tamsulosin groups. Blood pressure remained unchanged in normotensive patients, but significantly decreased in hypertensive patients except for the tamsulosin group. Adverse events were minimal in all treatment groups. Conclusions:The efficacy and safety profiles were different among the alpha-1 blockers at standard doses. Tamsulosin appears to be safer than the others for aged patients or patients with hypertension who have impaired blood pressure regulation, while terazosin is significantly effective in improving symptomatic score when compared with the others examined. It is recommended that the alpha-1 blocking agent and its optimal dose are selected on the basis of the baseline characteristics of the patients with symptomatic BPH.

Modeling of Relationships between Pharmacokinetics and Blockade of Agonist-Induced Elevation of Intraurethral Pressure and Mean Arterial Pressure in Conscious Dogs Treated with α1-Adrenoceptor Antagonists

“…These results are consistent with clinical data in which terazosin and doxazosin have been shown to be similarly potent and similarly efficacious agents for the treatment of symptomatic BPH, but with a similar frequency of cardiovascular side effects (Djavan and Merberger, 1999). Interestingly, clinical studies for tamsulosin indicated reduced incidence of cardiovascular side effects compared with terazosin and doxazosin (Lee and Lee, 1997;Djavan and Merberger, 1999;Schä fers et al, 1999;Tsujii, 2000). These observations support the hypothesis that cardiovascular side effects are primarily associated with blockade of ␣ 1b -adrenoceptors, whereas improvement of BPH symptoms is primarily associated with blockade of ␣ 1a -, and perhaps ␣ 1d -adrenoceptors (Testa et al, 1994;Take et al, 1998).…”

“…In the present study we compared the PK and PD properties of four ␣ 1 -adrenoceptor antagonists. These included the nonselective antagonists terazosin and doxazosin; the ␣ 1A -/␣ 1D -adrenoceptor-selective antagonist tamsulosin, reported in comparative studies to show uroselectivity (Lee and Lee, 1997;Schä fers et al, 1999;Tsujii, 2000); and a novel ␣ 1A -/ ␣ 1D -adrenoceptor-selective antagonist fiduxosin. PK/PD modeling of these data provide a basis for evaluating the potential uroselectivity of fiduxosin compared with nonselective ␣ 1 -antagonists.…”

Prazosin: Benign Prostatic Hyperplasia

“…2 No studies have been published regarding the use of prazosin in BPH management since the American Urology Association (AUA) published BPH guidelines. 1…”

Tamsulosin Versus Terazosin for Benign Prostatic Hyperplasia: A Systematic Review

“…The patient characteristic baselines were comparable as shown in Table 1. [Suzuki et al 2001;Okada et al 2000;Na et al 1998;Lee and Lee 1997;Narayan et al 2005;Tsujii 2000;Zhong et al 2000;Hou et al 1999;Jing 1999;Xu et al 2000;Na et al 1996;Lu 1998]. These 12 trials all reported adverse effects including dizziness, severe hypotension, dry mouth.…”