Description

Proscar (finasteride 5 mg)

Proscar contains finasteride 5 mg and is used for benign prostatic hyperplasia (BPH) in men with prostate glands enlarged to 30 ml or more. It’s also used for male-pattern hair loss at a lower dose (1 mg, sold as Propecia) — Proscar at 5 mg is the BPH formulation. The drug inhibits 5-alpha reductase type 2, slowing the conversion of testosterone to DHT in the prostate. Reduced DHT causes the prostate to shrink gradually, improving urinary flow and reducing symptoms of outlet obstruction.

Dosing

One 5 mg tablet daily, taken with or without food. Results are not immediate: symptom improvement typically takes 2 to 6 months to develop; some men don’t see maximum benefit for 6 to 12 months. Missing a dose is managed by taking it later that day — not by doubling the next day’s dose. Long-term treatment is required to maintain effect; stopping reverses the prostate size reduction.

Contraindications

Women of childbearing age must not handle Proscar tablets, particularly if broken or crushed — finasteride is absorbed through skin and causes abnormal development of male fetal external genitalia. This is an absolute contraindication. Finasteride should not be used by anyone with hypersensitivity to it or to its excipients.

PSA and prostate cancer screening

Finasteride reduces PSA levels by approximately 50% after six months of treatment. Any PSA result in a man taking finasteride should be doubled to approximate the true baseline. Failure to account for finasteride-induced PSA suppression can delay detection of prostate cancer. All clinicians involved in prostate monitoring should know the patient is taking this medication.

Sexual side effects

Decreased libido and erectile dysfunction occur in approximately 4% of men taking finasteride for BPH. Ejaculation disorders and gynecomastia have also been reported. The label notes that these effects are generally reversible upon stopping treatment, but persistent sexual dysfunction after stopping has been documented in some patients and should be discussed before initiating long-term therapy.

Side effects

Beyond sexual effects, finasteride 5 mg is generally well tolerated. Hormonal effects including gynecomastia and, less frequently, breast tenderness can occur. No clinically relevant drug interactions with finasteride have been established.