Finasterideside effects
finasteride 5 MG Oral Tablet
Adverse reactions
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. 4-Year Placebo-Controlled Study (A Long-Term Efficacy and Safety Study) In A Long-Term Efficacy and Safety Study, 1,524 patients treated with finasteride tablets and 1,516 patients treated with placebo were evaluated for safety over a period of 4 years. The most frequently reported adverse reactions were related to sexual function. 3.7% (57 patients) treated with finasteride tablets 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 1 presents the only clinical adverse reactions considered possibly, probably or definitely drug related by the investigator, for which the incidence on finasteride 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 difference between treatment groups in the incidences of impotence, decreased libido and ejaculation disorder.
Table 1: Drug-Related Adverse Experiences Year 1 (%) Years 2, 3 and 4*(%) Finasteride Placebo Finasteride Placebo Impotence 8.1 3.7 5.1
5.1 Decreased
Libido 6.4 3.4 2.6
2.6 Decreased
Volume of Ejaculate 3.7 0.8 1.5
0.5 Ejaculation
Disorder 0.8 0.1 0.2 0.1 Breast Enlargement 0.5 0.1 1.8 1.1 Breast Tenderness 0.4 0.1 0.7 0.3 Rash 0.5 0.2 0.5 0.1 *Combined Years 2 to 4 N = 1,524 and 1,516, finasteride vs placebo, respectively Phase III Studies and 5-Year Open Extensions The adverse experience profile in the 1-year, placebo-controlled, Phase III studies, the 5-year open extensions, and A Long-Term Efficacy and Safety Study were similar. Medical Therapy of Prostatic Symptoms (MTOPS) Study In the MTOPS study, 3,047 men with symptomatic BPH were randomized to receive finasteride tablets 5 mg/day (n=768), doxazosin 4 or 8 mg/day (n=756), the combination of finasteride tablets 5 mg/day and doxazosin 4 or 8 mg/day (n=786), or placebo (n=737) for 4 to 6 years. The incidence rates of drug-related adverse experiences reported by ≥2% of patients in any treatment group in the MTOPS Study are listed in Table 2. The individual adverse effects which occurred more frequently in the combination group compared to either drug alone were: asthenia, postural hypotension, peripheral edema, dizziness, decreased libido, rhinitis, abnormal ejaculation, impotence and abnormal sexual function (see Table 2). Of these, the incidence of abnormal ejaculation in patients receiving combination therapy was comparable to the sum of the incidences of this adverse experience reported for the two monotherapies. Combination therapy with finasteride and doxazosin was associated with no new clinical adverse experience. Four patients in MTOPS reported the adverse experience breast cancer. Three of these patients were on finasteride only and one was on combination therapy. The MTOPS Study was not specifically designed to make statistical comparisons between groups for reported adverse experiences. In addition, direct comparisons of safety data between the MTOPS study and previous studies of the single agents may not be appropriate based upon differences in patient population, dosage or dose regimen, and other procedural and study design elements. Adverse Experience Placebo (N=737) (%) Doxazosin 4 mg or 8 mg* (N=756) (%) Finasteride (N=768) (%) Combination (N=786) (%) Table 2: Incidence ≥2% in One or More Treatment Groups Drug-Related Clinical Adverse Experiences in MTOPS Body as a whole Asthenia 7.1 15.7 5.3 16.8 Headache 2.3 4.1 2.0
2.3 Cardiovascular
Hypotension 0.7 3.4 1.2
1.5 Postural
Hypotension 8.0 16.7 9.1
17.8 Metabolic and
Nutritional Peripheral Edema 0.9 2.6 1.3
3.3 Nervous
Dizziness 8.1 17.7 7.4 23.2 Libido Decreased 5.7 7.0 10.0 11.6 Somnolence 1.5 3.7 1.7
3.1 Respiratory
Dyspnea 0.7 2.1 0.7 1.9 Rhinitis 0.5 1.3 1.0
2.4 Urogenital
Abnormal Ejaculation 2.3 4.5 7.2 14.1 Gynecomastia 0.7 1.1 2.2 1.5 Impotence 12.2 14.4 18.5
22.6 Sexual Function
Abnormal 0.9 2.0 2.5 3.1 * Doxazosin dose was achieved by weekly titration (1 to 2 to 4 to 8 mg). The final tolerated dose (4 mg or 8 mg) was administered at end-Week 4. Only those patients tolerating at least 4 mg were kept on doxazosin. The majority of patients received the 8-mg dose over the duration of the study. Long-Term Data High-Grade Prostate Cancer The PCPT trial was a 7-year randomized, double-blind, placebo-controlled trial that enrolled 18,882 men ≥55 years of age with a normal digital rectal examination and a PSA ≤3.0 ng/mL. Men received either finasteride 5 mg or placebo daily. Patients were evaluated annually with PSA and digital rectal exams. Biopsies were performed for elevated PSA, an abnormal digital rectal exam, or the end of study. The incidence of Gleason score 8 to 10 prostate cancer was higher in men treated with finasteride (1.8%) than in those treated with placebo (1.1%). In a 4-year placebo-controlled clinical trial with another 5α-reductase inhibitor (dutasteride, AVODART), similar results for Gleason score 8 to 10 prostate cancer were observed (1% dutasteride vs 0.5% placebo). No clinical benefit has been demonstrated in patients with prostate cancer treated with finasteride tablets. Breast Cancer During the 4- to 6-year placebo- and comparator-controlled MTOPS study that enrolled 3,047 men, there were 4 cases of breast cancer in men treated with finasteride but no cases in men not treated with finasteride. During the 4-year, placebo-controlled A Long-Term Efficacy and Safety Study that enrolled 3,040 men, there were 2 cases of breast cancer in placebo-treated men but no cases in men treated with finasteride. During the 7-year placebo-controlled Prostate Cancer Prevention Trial (PCPT) that enrolled 18,882 men, there was 1 case of breast cancer in men treated with finasteride, and 1 case of breast cancer in men treated with placebo. The relationship between long-term use of finasteride and male breast neoplasia is currently unknown. Sexual Function There is no evidence of increased sexual adverse experiences with increased duration of treatment with finasteride tablets. New reports of drug-related sexual adverse experiences decreased with duration of therapy.
6.2 Postmarketing
Experience The following additional adverse events have been reported in postmarketing experience with finasteride tablets. Because these events are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure: - hypersensitivity reactions, such as pruritus, urticaria, and angioedema (including swelling of the lips, tongue, throat, and face) - testicular pain -hematospermia - sexual dysfunction that continued after discontinuation of treatment, including erectile dysfunction, decreased libido and ejaculation disorders (e.g. reduced ejaculate volume). These events were reported rarely in men taking finasteride tablets for the treatment of BPH. Most men were older and were taking concomitant medications and/or had co-morbid conditions. The independent role of finasteride tablets in these events is unknown. - male infertility and/or poor seminal quality were reported rarely in men taking finasteride tablets for the treatment of BPH. Normalization or improvement of poor seminal quality has been reported after discontinuation of finasteride. The independent role of finasteride tablets in these events is unknown. - depression - male breast cancer. The following additional adverse event related to sexual dysfunction that continued after discontinuation of treatment has been reported in postmarketing experience with finasteride at lower doses used to treat male pattern baldness. Because the event is reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate its frequency or establish a causal relationship to drug exposure: - orgasm disorders
Text above is quoted in full from the FDA-approved drug label published by openFDA, effective December 16, 2025. Matched to this product by RxNorm code. Cross-references to other sections of the full prescribing information have been removed, since they point to a document not shown here. Nothing else is changed: no sentence is shortened, reworded or summarised.
Contraindications
Finasteride tablets are contraindicated in the following: Hypersensitivity to any component of this medication. Pregnancy. Finasteride use is contraindicated in females 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 female who receives finasteride. If this drug is used during pregnancy, or if pregnancy occurs while taking this drug, the pregnant female should be apprised of the potential hazard to the male fetus. In female rats, low doses of finasteride administered during pregnancy have produced abnormalities of the external genitalia in male offspring.
Text above is quoted in full from the FDA-approved drug label published by openFDA, effective December 16, 2025. Matched to this product by RxNorm code. Cross-references to other sections of the full prescribing information have been removed, since they point to a document not shown here. Nothing else is changed: no sentence is shortened, reworded or summarised.
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