From the Guidelines
The recommended dose of finasteride for the treatment of benign prostatic hyperplasia (BPH) is 5 mg taken orally once daily. This dose has been shown to be effective in reducing prostate size and improving urinary symptoms in BPH patients, with symptom improvement typically occurring within 3-6 months of treatment initiation 1. Finasteride works by inhibiting the enzyme 5-alpha-reductase, which converts testosterone to dihydrotestosterone (DHT), a hormone that contributes to prostate enlargement. By reducing DHT levels, finasteride helps reduce prostate size and improve urinary symptoms in BPH patients.
Some key points to consider when prescribing finasteride for BPH include:
- The medication's slow onset of action, with patients typically experiencing symptom improvement within 3-6 months of treatment initiation 1
- The importance of counseling patients on the potential for slower symptom improvement compared to alpha blockers 1
- The need for continued use to maintain benefits, with improvements in standardized symptom scores (e.g., IPSS) maintained for 6-10 years of follow-up 1
- The potential for common side effects, including decreased libido, erectile dysfunction, and decreased ejaculate volume, which occur in a small percentage of users 1
It is also important to note that finasteride has been shown to be effective in reducing the risk of clinical progression (as defined by increase in IPSS, AUR, UTI, or BPH-related surgery) in men with BPH, with a study demonstrating a reduction in clinical progression from 36% to 21% compared to placebo 1. Additionally, finasteride has been shown to alter the natural history of BPH, with the PLESS study suggesting that 5-ARI therapy can be utilized in appropriately enlarged prostates as prevention for BPH 1.
From the FDA Drug Label
Finasteride tablets may be administered with or without meals. 2.1 Monotherapy The recommended dose of finasteride tablet is one tablet (5 mg) taken once a day [see CLINICAL STUDIES (14.1)]. 2.2 Combination with Alpha-Blocker The recommended dose of finasteride tablet is one tablet (5 mg) taken once a day in combination with the alpha-blocker doxazosin [see CLINICAL STUDIES (14.2)]. The recommended dose of finasteride is 5 mg taken once a day, either as monotherapy or in combination with an alpha-blocker 2.
- The dose is the same for both monotherapy and combination therapy.
- The dosage frequency is once daily.
From the Research
Finasteride Dose
- The standard dose of finasteride for the treatment of benign prostatic hyperplasia (BPH) is 5 mg per day 3, 4.
- For the treatment of male androgenetic alopecia, the standard dose is 1 mg per day 5, 6.
Efficacy and Safety
- Finasteride has been shown to be effective in reducing symptoms of BPH, improving urinary flow, and decreasing prostatic volume 3, 4.
- The drug is generally well tolerated, with common adverse effects being sexually related, such as decreased libido, impotence, and ejaculatory disorders 3, 4, 6.
Comparison of Doses
- A study comparing 1 mg and 5 mg doses of finasteride found that the 5 mg dose was more effective in reducing symptoms of BPH and improving urinary flow 3.
- However, the 1 mg dose was still effective in improving urinary flow and reducing prostatic volume, although to a lesser extent than the 5 mg dose 3.