Benign prostatic hyperplasia finasteride

Kaplan SA, Chung DE, Lee RK, Scofield S, Te AE. A 5-year retrospective analysis of 5a-reductase inhibitors in men with benign prostatic hyperplasia finasteride has comparable urinary symptom efficacy and prostate volume reduction, but less sexual side effects and breast complications than dutasteride. Int J Clin Pract 2012 66(ll) 1052-5. 

McConnell JD, Roehrborn CG, Bautista OM et al. The long term effect of doxazosin, finasteride, and combination therapy on the clinical progression of benign prostatic hyperplasia. N Engl 1 Med 2003 349 2387-2398. 

Unfortunately, not all products that are used in clinical trials are available in the United States. In a randomized, double-blind, multicenter European study, 1069 men with moderate benign prostatic hyperplasia were randomized to receive saw palmetto (Permixon" )1 160 mg twice daily (90% free and 7% esterified fatty acids) or finasteride 5 mg once daily for 6 months [32]. As determined by patients and physicians, Permixon offered similar improvement in symptoms related to benign prostatic hyperplasia compared to finasteride. Since Permixon is not available in the United States, it should be recommended to patients to use a product that is similar to Permixon that contains a standardized extract of saw palmetto containing 85-95% sterols and fatty acids [18]. 

Carraro JC, Raynaud JP, Koch G, et al. Comparison of phytotherapy (Permixon) with finasteride in the treatment of benign prostate hyperplasia a randomized international study of 1098 patients. Prostate 4 231-240, 1996. 

Benign prostatic hyperplasia 1-2 mg qhs orthostatic hypotension initially more effective than finasteride. 

Finasteride inhibits 5a-reductase, the enzyme converting T. into dihydrotestosterone (DHT). Thus, the androgenic stimulus is reduced in those tissues in which DHT is the active species (e.g., prostate). T.-dependent tissues or functions are not or hardly affected (e.g., skeletal muscle, negative feedback inhibition of gonadotropin secretion, and libido). Finasteride can be used in benign prostate hyperplasia to shrink the gland and, possibly, to improve micturition. 

Geriatric Considerations - Summary Alpha-adrenergic blockers are modestly effective alone, and in combination with 5-alpha reductase inhibitors (e,g, finasteride) in the treatment of urinary obstructive symptoms related to benign prostatic hyperplasia. Alfuzosin is a "uroselective" alpha-blockerwhich appears to cause less orthostatic hypotension than nonselective alpha-blockers such as terazosin, prazosin, and doxazosin. 

Lepor H, Williford WO, Barry MJ, et al. The efficacy of terazosin, finasteride, or both in benign prostatic hyperplasia. Veterans Affairs Cooperative Studies Benign Prostatic Hyperplasia Study Group. N Engl I Med 1996 335 533-539. 

Finasteride is a selective inhibitor of 5-alpha-reductase. It thereby reduces prostatic concentrations of dihydrotestosterone and so reduces prostatic size (6,7,8). It is therefore used to treat benign prostatic hyperplasia (9,10,11,12) and in the prevention and treatment of prostate cancer (13). It is poorly effective in patients with prostatic obstruction and small prostate glands (14), but in patients with glands larger than 40 ml it produces significant symptomatic improvement. 

The benefit of combining an alpha-adrenoceptor antagonist with a 5-alpha-reductase inhibitor has been assessed in men with benign prostatic hyperplasia (23). Modified-release alfuzosin was more effective than finasteride, with no additional benefit in combining the drugs. The adverse effects of alpha-blockade were postural hypotension, hypotension, headache, dizziness, and malaise the adverse effects of finasteride were ejaculatory disorders and impotence. 

The therapeutic and adverse effects of dibenyline, finasteride, and a combination of the two in 190 patients with symptomatic benign prostatic hyperplasia have been evaluated (24). Adverse effects were more common with dibenyline than with finasteride alone or in combination with dibenyline. The drop-out rate was higher with dibenyline (16%) than finasteride alone (7.5%) or the two in combination (4.6%). The reported adverse effects are listed in Table 1. 

Table 1 Adverse effect of finasteride with or without dibenyline in benign prostatic hyperplasia...

In a Spanish systematic review of the world literature there were firm conclusions about the value of finasteride in reducing the symptoms of benign prostatic hyperplasia in doses that are well tolerated in all respects (36). 

There is a higher incidence of impaired sexual function in men who take finasteride compared with placebo (58,59). The incidence of erectile dysfunction has been estimated at 5% (60), but it is difficult to estimate, since in many users of the drug other causes are present, including advanced age, heart disease, diabetes, hypertension, smoking, and hypercholesterolemia. Benign prostatic hyperplasia itself can also aggravate or even induce erectile dysfunction. A questionnaire study in New Jersey... 

The long-term efficacy and safety of finasteride have been studied in 102 patients with benign prostatic hyperplasia (62). Adverse experiences due to sexual dysfunction continued throughout the study, but the low continuous dropout rate may have reflected a natural process in this aged population, and not necessarily a drug-related effect. 

The effects of finasteride (n = 545), tamsulosin, or the proprietary herbal remedy Permixon on sexual function have been studied in patients with lower urinary tract symptoms due to benign prostatic hyperplasia (64). At 6 months tamsulosin and finasteride caused slight increases in sexual disorders and Permixon caused a slight improvement. Ejaculation disorders were the most frequently reported adverse effects after tamsulosin or finasteride. 

Striking evidence of the association of finasteride with male breast cancer comes from the Medical Therapy of Prostatic Symptoms (MTOPS) study, a National Institutes of Health (NIH)-sponsored study of about 3047 men that compared finasteride, doxazosin, and the combination for the treatment of benign prostatic hyperplasia. The rate of breast cancer in this trial for men taking finasteride either alone or with doxazosin was four in 1554, or nearly 200 times that of the general population one man in the finasteride + doxazosin group and three in the finasteride-alone group developed male breast cancer (74). 

In 3040 men with benign prostatic hyperplasia the effects of finasteride 5 mg/day for 4 years were studied in those over and under 65 years (78). In both groups the drug was effective and there were no significant differences in cardiovascular adverse events between placebo and finasteride. There were significant differences between placebo and finasteride in the overall incidence of typical drug-related adverse events, but there were no specific differences associated with age. The principal events were impotence (8.8%), reduced libido (6.8%), reduced volume of ejaculate (3.5%), other disorders of ejaculation (1.5%), rash (0.6%), breast enlargement (0.5%), and breast tenderness (0.2%). 

Peters DH, Sorkin EM. Finasteride. A review of its potential in the treatment of benign prostatic hyperplasia. Drugs 1993 46(l) 177-208. 

Nickel JC, Fradet Y, Boake C, Pommerville PJ, Perreault J-P, Afridi SK, Elhilali MM, Barr RE, Beland GA, Bertrand PE, et al. Efficacy and safety of finasteride therapy for benign prostatic hyperplasia results of a 2-year randomized controlled trial (the PROSPECT study). Can Med Assoc J 1996 155 1251-9. 

Edwards JE, Moore RA. Finasteride in the treatment of clinical benign prostatic hyperplasia a systematic review of randomised trials. BMC Urol 2002 2 14. 

Ekman P. A risk-benefit assessment of treatment with finasteride in benign prostatic hyperplasia. Drug Saf 1998 18 161-70. 

De Bruyne FMJ, Jardin A, Colloi D, Resel L, Witjes WPJ, Delauche-Cavallier MC, McCarthy C, Geffriaud-Ricouard C. Sustained release alfuzosin, finasteride and the combination of both in the treatment of benign prostatic hyperplasia. Eur Urol 1998 34 169-75. 

Kuo HC. Comparative study for therapeutic effect of dibenyline, finasteride and combination drugs for symptomatic benign prostatic hyperplasia. Urol Int 1998 60 85-91. 

Carraro JC, Raynaud JP, Koch G, Chisholm GD, Di Silverio F, Teillac P, Da Silva FC, Cauquil J, Chopin DK, Hamdy FC, Hanus M, Hauri D, Kalinteris A, Marencak J, Perier A, Perrin P. Comparison of phytotherapy (Permixon) with finasteride in the treatment of benign prostate hyperplasia a randomized international study of 1,098 patients. Prostate I996 29(4) 23 I K). 

Byrnes CA, Morton AS, Liss CL, Lippert MC, Gillenwater JY. Efficacy, tolerability, and effect on health-related quality of life of finasteride versus placebo in men with symptomatic benign prostatic hyperplasia a community based study. CUSP Investigators. Community based study of Proscar. Clin Ther 1995 17 956-69. 

Margerger MJ. Long-term effects of finasteride in patients with benign prostatic hyperplasia a double-blind, placebo-controlled multicenter study. Urology 1998 51 677-86. 

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