What is Finasteride?
Finasteride is a treatment for hair loss in men, or male pattern baldness, as it’s sometimes known. It prevents hormone conversion in the body that causes hair follicles to shrink, triggering hair loss.
It’s also used to treat men with an enlarged prostate, or benign prostate enlargement (or BPH for short).
Sometimes Finasteride can even trigger hair regrowth, although it needs to be taken on a long-term basis for you to keep getting positive results from it.
Male pattern baldness is usually pretty easy to identify. You can start to lose hair from the scalp or top of the head, but it can also start at the front of the head, which is what’s known as a receding hairline.
How does Finasteride work?
There’s an enzyme in the body called 5-alpha reductase. It converts the hormone testosterone into another hormone, dihydrotestosterone, or DHT. DHT can make hair follicles shrink, and trigger hair loss, if your body is sensitive to it.
Finasteride stops the enzyme from converting testosterone into DHT, reducing the amount of the enzyme in the blood and the scalp. This helps to bolster hair growth, and prevent any more hair loss.
How long does Finasteride take to work?
It starts working in the body immediately, so it’s likely that your DHT levels will be lower as soon as you’ve taken your first dose. Generally speaking, Finasteride reduces DHT in the body by around 70%.
But it can take longer before you see any results. Because male pattern hair loss is a condition that develops slowly, it may take between 3 and 6 months before you see any improvement in the thickness of your hair, or any reduction in hair loss, with Finasteride. And it may be up to 12 months before you see the best results.
It’s easy to stop taking Finasteride if you’re not noticing any improvements relatively quickly, but you should keep taking it as prescribed. Your DHT levels will return to normal if you interrupt your course of treatment, and you may start to lose hair once more. Patience can be the key with it.
It’s also important to note that Finasteride doesn’t always trigger hair regrowth. It’s a treatment that’s often taken to stop any further loss of hair, rather than as a means of getting hair to grow back.
Your hair will still fall out when you’re using Finasteride as part of its natural growth cycle (stray hairs being replaced by new hairs), so you’ll continue to see stray hairs in the shower or the bath, on your comb, or in your hands. This is totally normal and nothing to worry about.
This page was medically reviewed by
Ms Laurenmarie Cormier, Clinical Content Reviewer on August 02, 2022. Next review due on August 01, 2025.
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