Proscar Side Effects

PROSCAR is well tolerated.
In PLESS, 1524 patients treated with PROSCAR 5 mg daily and 1516 patients treated with placebo were evaluated for safety over a period of 4 years. 4.9% (74 patients) were discontinued from treatment due to side effects associated with PROSCAR compared with 3.3% (50 patients) treated with placebo. 3.7% (57 patients) treated with PROSCAR and 2.1% (32 patients) treated with placebo discontinued therapy as a result of side effects related to sexual function, which were the most frequently reported side effects.
The only clinical adverse reactions considered possibly, probably or definitely drug related by the investigator, for which the incidence on PROSCAR was ≥1% and greater than placebo over the 4 years of the study, were those related to sexual function, breast complaints and rash. In the first year of the study, impotence was reported in 8.1% of patients treated with PROSCAR vs. 3.7% of those treated with placebo; decreased libido was reported in 6.4 vs. 3.4%, and ejaculation disorder in 0.8 vs. 0.1%, respectively. In years 2-4 of the study, there was no significant difference between treatment groups in the incidences of these three effects. The cumulative incidences in years 2-4 were: impotence (5.1% on PROSCAR, 5.1% on placebo); decreased libido (2.6%, 2.6%); and ejaculation disorder (0.2%, 0.1%). In year 1, decreased volume of ejaculate was reported in 3.7 and 0.8% of patients on PROSCAR and placebo, respectively; in years 2-4 the cumulative incidence was 1.5% on PROSCAR and 0.5% on placebo. In year 1, breast enlargement (0.5%, 0.1%), breast tenderness (0.4%, 0.1%) and rash (0.5%, 0.2%) were also reported. In years 2-4 the cumulative incidences were: breast enlargement, (1.8%, 1.1%); breast tenderness, (0.7%, 0.3%); and rash (0.5%, 0.1%).
The adverse experience profile in the 1-year, placebo-controlled, Phase III studies and the 5-year extensions, including 853 patients treated for 5-6 years, was similar to that reported in years 2-4 in PLESS. There is no evidence of increased adverse experiences with increased duration of treatment with PROSCAR. The incidence of new drug-related sexual adverse experiences decreased with duration of treatment.
Other Long-Term Data: PROSCAR may increase the risk of high-grade prostate cancer. In a 7-year placebo-controlled trial that enrolled 18,882 healthy men, of whom 9060 had prostate needle biopsy data available for analysis, prostate cancer was detected in 803 (18.4%) men receiving PROSCAR and 1147 (24.4%) men receiving placebo. In the PROSCAR group, 280 (6.4%) men had prostate cancer with Gleason scores of 7-10 detected on needle biopsy vs. 237 (5.1%) men in the placebo group. Additional analyses suggest that the increase in the prevalence of high-grade prostate cancer observed in the PROSCAR group may be explained by a detection bias due to the effect of PROSCAR on prostate volume. Of the total cases of prostate cancer diagnosed in this study, approximately 98% were classified as intracapsular (clinical stage T1 or T2) at diagnosis. The clinical significance of the Gleason 7-10 data is unknown.
Breast Cancer: During the 4- to 6-year placebo- and comparator-controlled MTOPS study that enrolled 3047 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 PLESS study that enrolled 3040 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. Post-marketing cases of male breast cancer have been reported with the use of finasteride. The relationship between long-term use of finasteride and male breast neoplasia is currently unknown.
Postmarketing Experience: The following additional adverse effects have been reported in post-marketing experience with PROSCAR and/or finasteride at lower doses. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate the frequency or establish a causal relationship to drug exposure.
Immune system disorders: hypersensitivity reactions, such as pruritus, urticaria and angioedema (including swelling of the lips, tongue, throat, and face).
Psychiatric disorders: depression; decreased libido that continued after discontinuation of treatment.
Reproductive system and breast disorders: sexual dysfunction (erectile dysfunction and ejaculation disorder) that continued after discontinuation of treatment. Erectile dysfunction (ED) that continued after discontinuation of treatment, reported rarely in men taking PROSCAR for the treatment of BPH. Most men were older and were taking concomitant medications and/or had co-morbid conditions with a known association to ED. The independent role of PROSCAR in these events is unknown; testicular pain; hematospermia; male infertility and/or poor seminal quality have been reported rarely in men taking PROSCAR for the treatment of BPH. The independent role of PROSCAR in these events is unknown. Normalization or improvement of seminal quality has been reported after discontinuation of finasteride.
Laboratory Test Findings: When PSA laboratory determinations are evaluated, consideration should be given to the fact that PSA levels are decreased in patients treated with PROSCAR (See Precautions).
No other difference in standard laboratory parameters was observed between patients treated with placebo or PROSCAR.