prostate cancer prophylaxis †
† non-FDA-approved indication
Finasteride (Propecia) Indications and Dosage
For the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate to improve symptoms, to reduce the risk of acute urinary retention, and to reduce the risk of the need for surgery including transurethral resection of the prostate (TURP) and prostatectomy:
Oral dosage (Proscar®):
Adult males, including elderly males: 5 mg PO once daily. A minimum of 6 months therapy may be necessary to assess response, with up to 12 months necessary in some patients. In a double-blind, randomized, placebo-controlled study, 3040 men with moderate to severe urinary symptoms and enlarged prostate were treated with finasteride 5 mg PO once daily or placebo for four years. Finasteride reduced BPH symptoms and prostate volume, increased the urinary flow rate, and reduced the probability of surgery and acute urinary retention. In a long-term, double-blind clinical trial of 3047 men with BPH, combination therapy of doxazosin (4 - 8 mg PO qd) and finasteride (5 mg PO qd) was shown to significantly reduce the risk of overall clinical progression of BPH than either drug alone. However, further study is required.
- for prostate cancer prophylaxis † :
Oral dosage (Proscar®):
Adult males, including elderly males: The role of finasteride in the prevention of prostate cancer has not been defined. In a 7-year placebo-controlled study, finasteride 5 mg PO once daily was shown to prevent or delay the development of prostate cancer in healthy men (>= 55 years of age) with a low risk of prostate cancer (PSA <= 3 ng/ml). Prostate specific antigen (PSA) levels, digital rectal exams, and biopsies were used to aid in the diagnosis of prostate cancer. Finasteride reduced the prevalence of prostate cancer by 24.8% relative to placebo. However, a higher rate of high-grade prostate cancer was noted in the finasteride group (6.4%, n=9423) compared to the placebo group (5.1%, n=9457); ); more data are needed to determine finasteride’s role in prostate CA prevention. Finasteride was associated with a higher incidence of sexual side effects versus placebo.
For the treatment of male pattern hair loss (i.e., androgenetic alopecia), in patients with mild to moderate hair loss of the vertex and anterior mid-scalp area:
Oral dosage (Propecia®):
Adult males, including elderly males: 1 mg PO once daily. Daily use for >= 3 months is necessary before benefit is observed. Continued use is recommended to sustain benefit. Withdrawal of treatment leads to reversal of effect within 12 months.
Maximum Dosage Limits:
- Adult males: 5 mg/day PO for benign prostatic hyperplasia (BPH); 1 mg/day PO for alopecia.
- Elderly males: 5 mg/day PO for benign prostatic hyperplasia (BPH); 1 mg/day PO for alopecia.
- Adolescents: Not indicated.
- Children: Not indicated.
Patients with hepatic impairment:
Finasteride should be initiated with caution in patients with hepatic disease. Since finasteride is metabolized extensively in the liver, reduced metabolism is possible. The effect of hepatic impairment on finasteride pharmacokinetics has not been studied.
Patients with renal impairment:
Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.
† non-FDA-approved indication
[ Last revised: 6/7/2004 12:32:00 PM ]
References
. McConnell JD, Bruskewitz R, Walsh P et al. The effect of finasteride on the risk of acute urinary retention and the need for surgical treatment among men with benign prostatic hyperplasia. N Engl J Med 1998;338:557 - 63.
. Thompson IM, Goodman PJ, Tangen CM, et al. The influence of finasteride on the development of prostate cancer. N Engl J Med 2003:349:213 - 22.
. 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 J Med 2003;349:2387 - 98.
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