Finasteride

FDA Drug Information • Also known as: Finasteride, Propecia, Proscar

Brand Names
Finasteride, Propecia, Proscar
Drug Class
5-alpha Reductase Inhibitor [EPC]
Route
ORAL
Dosage Form
TABLET, FILM COATED
Product Type
HUMAN PRESCRIPTION DRUG

Description

11 DESCRIPTION Finasteride tablets USP, 1 mg contains finasteride as the active ingredient. Finasteride USP, a synthetic 4-azasteroid compound, is a specific inhibitor of steroid Type II 5α-reductase, an intracellular enzyme that converts the androgen testosterone in to 5α-dihydrotestosterone (DHT). Finasteride is 4-azaandrost-1-ene-17-carboxamide, N-(1,1-dimethylethyl)-3-oxo-, (5α, 17β)-. The empirical formula of finasteride is C 23 H 36 N 2 O 2 and its molecular weight is 372.55. Its structural formula is: Finasteride is a white crystalline powder with a melting point near 250° C. It is freely soluble in chloroform and in lower alcohol solvents but is practically insoluble in water. Finasteride tablets USP for oral administration are film-coated tablets that contain 1 mg of finasteride and the following inactive ingredients: lactose monohydrate, microcrystalline cellulose, pregelatinized starch, sodium starch glycolate, docusate sodium, magnesium stearate and opadry brown (hypromellose, iron oxide red, talc, titanium dioxide, yellow iron oxide). structure6

What Is Finasteride Used For?

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 ).

  • Dosage and Administration

    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 ).

  • Side Effects (Adverse Reactions)

    6 ADVERSE REACTIONS The most common adverse reactions, 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 ADVERSE REACTIONS, 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. Two other studies showed that finasteride at 5 times the dosage of finasteride tablets USP (5 mg daily) produced significant median decreases of approximately 0.5 mL (-25%) compared to placebo in ejaculate volume, but this was reversible after discontinuation of treatment. In the clinical studies with finasteride tablets USP, the incidences for breast tenderness and enlargement, hypersensitivity reactions, and testicular pain in finasteride-treated patients were not different from those in patients treated with placebo. Controlled Clinical Trials and Long-Term Open Extension Studies for finasteride tablets USP, 5 mg and AVODART (dutasteride) in the Treatment of Benign Prostatic Hyperplasia In the finasteride tablets USP, 5 mg Long-Term Efficacy and Safety Study (PLESS), a 4-year controlled clinical study, 3040 patients between the ages of 45 and 78 with symptomatic BPH and an enlarged prostate were evaluated for safety over a period of 4 years (1524 on finasteride tablets USP, 5 mg/day and 1516 on placebo). 3.7% (57 patients) treated with finasteride tablets USP, 5 mg and 2.1% (32 patients) treated with placebo discontinued therapy as a result of adverse reactions related to sexual function, which are the most frequently reported adverse reactions. Table 2 presents the only clinical adverse reactions considered possibly, probably or definitely drug related by the investigator, for which the incidence on finasteride tablets USP, 5 mg was ≥1% and greater than placebo over the 4 years of the study. In years 2 to 4 of the study, there was no significant...

    Drug Interactions

    7 DRUG INTERACTIONS 7.1 Cytochrome P450-Linked Drug Metabolizing Enzyme System No drug interactions of clinical importance have been identified. Finasteride does not appear to affect the cytochrome P450-linked drug-metabolizing enzyme system. Compounds that have been tested in man include antipyrine, digoxin, propranolol, theophylline, and warfarin and no clinically meaningful interactions were found. 7.2 Other Concomitant Therapy Although specific interaction studies were not performed, finasteride doses of 1 mg or more were concomitantly used in clinical studies with acetaminophen, acetylsalicylic acid, α-blockers, analgesics, angiotensin-converting enzyme (ACE) inhibitors, anticonvulsants, benzodiazepines, beta blockers, calcium-channel blockers, cardiac nitrates, diuretics, H 2 antagonists, HMG-CoA reductase inhibitors, prostaglandin synthetase inhibitors (also referred to as NSAIDs), and quinolone anti-infectives without evidence of clinically significant adverse interactions.

    Contraindications

    4 CONTRAINDICATIONS 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 Warnings and Precautions (5.1) , Use in Specific Populations (8.1) , How Supplied/Storage and Handling (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 ).

  • Pregnancy and Breastfeeding

    8.1 Pregnancy Teratogenic Effects : Pregnancy Category X [ see Contraindications (4) ]. Finasteride tablets USP is contraindicated for use in women who are or may become pregnant. Finasteride tablets USP are Type II 5α-reductase inhibitor that prevents conversion of testosterone to 5α-dihydrotestosterone (DHT), a hormone necessary for normal development of male genitalia. In animal studies, finasteride caused abnormal development of external genitalia in male fetuses. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the male fetus. Abnormal male genital development is an expected consequence when conversion of testosterone to 5α-dihydrotestosterone (DHT) is inhibited by 5α-reductase inhibitors. These outcomes are similar to those reported in male infants with genetic 5α-reductase deficiency. Women could be exposed to finasteride through contact with crushed or broken finasteride tablets or semen from a male partner taking finasteride tablets USP. With regard to finasteride exposure through the skin, finasteride tablets USP are coated and will prevent skin contact with finasteride during normal handling if the tablets have not been crushed or broken. Women who are pregnant or may become pregnant should not handle crushed or broken finasteride tablets USP because of possible exposure of a male fetus. If a pregnant woman comes in contact with crushed or broken finasteride tablets , the contact area should be washed immediately with soap and water. With regard to potential finasteride exposure through semen, a study has been conducted in men receiving finasteride tablets USP 1 mg/day that measured finasteride concentrations in semen [ see Clinical Pharmacology (12.3) ]. In an embryo-fetal development study, pregnant rats received finasteride during the period of major organogenesis (gestation days 6 to 17). At maternal doses of oral finasteride approximately 1 to...

    8.3 Nursing Mothers Finasteride tablets USP are not indicated for use in women. It is not known whether finasteride is excreted in human milk.

    Overdosage

    10 OVERDOSAGE In clinical studies, single doses of finasteride up to 400 mg and multiple doses of finasteride up to 80 mg/day for three months did not result in adverse reactions. Until further experience is obtained, no specific treatment for an overdose with finasteride can be recommended. Significant lethality was observed in male and female mice at single oral doses of 1500 mg/m 2 (500 mg/kg)and in female and male rats at single oral doses of 2360 mg/m 2 (400 mg/kg)and 5900 mg/m 2 (1000 mg/kg), respectively.

    How Supplied

    16 HOW SUPPLIED/STORAGE AND HANDLING Finasteride tab le t s USP, 1 mg, is brown color, round film coated tablets, debossed with ‘H’ on one side and ‘36’ on other side. They are supp lied as f o llo w s: NDC 31722-526-30 bottles of 30 NDC 31722-526-90 bottles of 90 NDC 31722-526-10 bottles of 1000 Storage and Handling Store at 20° to 25° C (68° to 77° F) [see USP Controlled Room Temperature]. Keep container closed and protect from moisture. Women should not handle crushed or broken finasteride tablets USP tablets when they are pregnant or may potentially be pregnant because of the possibility of absorption of finasteride and the subsequent potential risk to a male fetus. finasteride tablets USP are coated and will prevent contact with the active ingredient during normal handling, provided that the tablets are not broken or crushed [ see Warnings and Precautions (5.1) , Use in Specific Populations (8.1) and Patient Counseling Information (17.1) ] .

    About This Information

    This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.

    What are side effects?

    Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.

    What are drug interactions?

    Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.