Finasteride: What it does and when people use it

Finasteride is a prescription drug most people know for treating male pattern hair loss and an enlarged prostate (BPH). It blocks an enzyme (5-alpha-reductase) that converts testosterone into DHT, the hormone linked to hair thinning and prostate growth. For hair, it’s usually 1 mg daily; for BPH, doctors often prescribe 5 mg daily.

People try finasteride because it often stops further hair loss and can regrow some hair if taken consistently. For an enlarged prostate it can shrink the gland, ease urine flow, and lower the chance of needing surgery later. It doesn’t work overnight—expect to wait months to see a difference.

How to use finasteride safely

Start with the dose your doctor gives you and take it the same time each day. Common routine: 1 mg once daily for hair loss. Give it at least 3–6 months before judging effectiveness; many users notice improvement by 6–12 months. If it helps, most doctors recommend continuing to keep the benefits.

Before starting, tell your doctor about other meds, medical conditions, and if you’re planning to father a child. Finasteride can lower PSA levels used to screen for prostate cancer, so your doctor should note you’re taking it when interpreting PSA results.

Common side effects and what to watch for

Most people tolerate finasteride well, but side effects can happen. The ones reported most often are sexual: decreased libido, fewer or weaker erections, and reduced ejaculate volume. These effects are uncommon (often cited around a few percent of users) and many men see them resolve after stopping the drug. Mood changes and breast tenderness or enlargement have been reported and need medical attention.

Women who are pregnant or may become pregnant should never handle crushed or broken finasteride tablets—exposure can harm a male fetus. Children should not take finasteride.

If you get persistent sexual problems, signs of depression, breast lumps, nipple discharge, or any worrying symptom, stop the drug and contact your doctor right away. For minor concerns, a phone call to your prescriber can help decide whether to continue or switch treatments.

Practical tips: get a baseline check (including PSA if relevant), buy from a licensed source, and be wary of very cheap or unverified online sellers. If you’re trying to grow hair, pair finasteride with good hair care and realistic expectations—improvement is usually gradual, and stopping the drug typically reverses gains.

Want to try it? Talk to your healthcare provider about risks and benefits, set a review at 3–6 months, and track changes with photos so you can see slow improvements. That simple routine keeps things safe and makes it easier to judge if finasteride is right for you.