بروستريد 5مجم 30 كبسولة

12.1 Mechanism of Action Finasteride is a competitive and specific inhibitor of Type II 5α-reductase, an intracellular enzyme that converts the androgen testosterone into DHT. Two distinct isozymes are found in mice, rats, monkeys, and humans: Type I and II. Each of these isozymes is differentially expressed in tissues and developmental stages. In humans, Type I 5α-reductase is predominant in the sebaceous glands of most regions of skin, including scalp, and liver. Type I 5α-reductase is responsible for approximately one-third of circulating DHT. The Type II 5α-reductase isozyme is primarily found in prostate, seminal vesicles, epididymides, and hair follicles as well as liver, and is responsible for two-thirds of circulating DHT. In humans, the mechanism of action of finasteride is based on its preferential inhibition of the Type II isozyme. Using native tissues (scalp and prostate), in vitro binding studies examining the potential of finasteride to inhibit either isozyme revealed a 100-fold selectivity for the human Type II 5α-reductase over Type I isozyme (IC 50 =500 and 4.2 nM for Type I and II, respectively). For both isozymes, the inhibition by finasteride is accompanied by reduction of the inhibitor to dihydrofinasteride and adduct formation with NADP+. The turnover for the enzyme complex is slow (t 1/2 approximately 30 days for the Type II enzyme complex and 14 days for the Type I complex). Inhibition of Type II 5α-reductase blocks the peripheral conversion of testosterone to DHT, resulting in significant decreases in serum and tissue DHT concentrations. In men with male pattern hair loss (androgenetic alopecia), the balding scalp contains miniaturized hair follicles and increased amounts of DHT compared with hairy scalp. Administration of finasteride decreases scalp and serum DHT concentrations in these men. The relative contributions of these reductions to the treatment effect of finasteride have not been defined. By this mechanism, finasteride appears to interrupt a key factor in the development of androgenetic alopecia in those patients genetically predisposed.

1 INDICATIONS & USAGE Finasteride tablets USP are indicated for the treatment of male pattern hair loss (androgenetic alopecia) in MEN ONLY. Efficacy in bitemporal recession has not been established. Finasteride tablets USP are not indicated for use in women. • Finasteride tablets USP are 5α-reductase inhibitors indicated for the treatment of male pattern hair loss (androgenetic alopecia) in MEN ONLY ( 1 ). • Finasteride tablets USP are not indicated for use in women ( 1 , 4 , 5.1 ).

2 DOSAGE & ADMINISTRATION Finasteride tablets USP may be administered with or without meals. The recommended dose of finasteride tablets USP is one tablet (1 mg) taken once daily. In general, daily use for three months or more is necessary before benefit is observed. Continued use is recommended to sustain benefit, which should be re-evaluated periodically. Withdrawal of treatment leads to reversal of effect within 12 months. • Finasteride tablets USP may be administered with or without meals ( 2 ). • One tablet (1 mg) taken once daily ( 2 ). • In general, daily use for three months or more is necessary before benefit is observed ( 2 ).

The most common , reported in ≥1% of patients treated with finasteride tablets USP and greater than in patients treated with placebo are: decreased libido, erectile dysfunction and ejaculation disorder ( 6.1 ). To report SUSPECTED , contact Hetero Labs Limited at 866-495-1995 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . See 17 for PATIENT COUNSELING INFORMATION and FDA-approved patient labeling. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. Clinical Studies for Finasteride Tablets USP 1 mg in the Treatment of Male Pattern Hair Loss In three controlled clinical trials for finasteride tablets USP of 12-month duration, 1.4% of patients taking finasteride tablets USP (n=945) were discontinued due to adverse experiences that were considered to be possibly, probably or definitely drug-related (1.6% for placebo; n=934). Clinical adverse experiences that were reported as possibly, probably or definitely drug-related in ≥1% of patients treated with finasteride tablets USP or placebo are presented in Table 1. TABLE 1 Drug-Related Adverse Experiences for Finasteride Tablets USP, 1 mg in Year 1 (%) MALE PATTERN HAIR LOSS Finasteride tablets USP N=945 Placebo N=934 Decreased Libido 1.8 1.3 Erectile Dysfunction 1.3 0.7 Ejaculation Disorder (Decreased Volume of Ejaculate) 1.2 (0.8) 0.7 (0.4) Discontinuation due to drug-related sexual adverse experiences 1.2 0.9 Integrated analysis of clinical adverse experiences showed that during treatment with finasteride tablets USP 36 (3.8%) of 945 men had reported one or more of these adverse experiences as compared to 20 (2.1%) of 934 men treated with placebo (p=0.04). Resolution occurred in men who discontinued therapy with finasteride tablets USP due to these side effects and in most of those who continued therapy. The incidence of each of the above adverse experiences decreased to ≤0.3% by the fifth year of treatment with finasteride tablets USP. In a study of finasteride 1 mg daily in healthy men, a median decrease in ejaculate volume of 0.3 mL (-11%) compared with 0.2 mL (-8%) for placebo was observed after 48 weeks of treatment....

Finasteride tablets USP are contraindicated in the following: • Pregnancy. Finasteride use is contraindicated in women when they are or may potentially be pregnant. Because of the ability of Type II 5α-reductase inhibitors to inhibit the conversion of testosterone to 5α-dihydrotestosterone (DHT), finasteride may cause abnormalities of the external genitalia of a male fetus of a pregnant woman who receives finasteride. If this drug is used during pregnancy, or if pregnancy occurs while taking this drug, the pregnant woman should be apprised of the potential hazard to the male fetus. [ See (5.1) , (8.1) , How Supplied/ (16) and Patient Counseling Information (17.1) .] In female rats, low doses of finasteride administered during pregnancy have produced abnormalities of the external genitalia in male offspring. • Hypersensitivity to any component of this medication. • Pregnancy ( 4 , 5.1 , 8.1 , 16 ). • Hypersensitivity to any components of this product ( 4 ).