Experiences with
Finasteride

Finasteride is used to treat an enlarged prostate (benign prostate enlargement). It can help ease your symptoms if:

it's difficult to start peeing
you need to pee urgently or more often
it's difficult to empty your bladder completely

Finasteride is available on prescription only. It comes as tablets.

It can also be used to treat hair loss in men (male pattern baldness).

However, for hair loss you can only get finasteride on a private prescription. This means you'll need to pay the full cost of the medicine. It's not available on the NHS.

This medicine is generally not recommended for women. It might be prescribed by a specialist doctor but only in very rare cases.

Who can take finasteride

Most men aged 18 years old or over can take finasteride.

It's generally not recommended for women or children.

Who may not be able to take finasteride

Finasteride is not suitable for some people. To make sure it's safe for you, tell a doctor if you:

have ever had an allergic reaction to finasteride or any other medicine
have ever had depression or thoughts about harming yourself
have severe bladder problems
have liver problems

Dosage

For an enlarged prostate the usual dose of finasteride is 5mg, taken once a day.

For hair loss, the usual dose is 1mg, taken once a day.

How to take it

You can take finasteride with or without food.

It does not matter what time of day you take it, just make sure it's around the same time each day.

Swallow your finasteride tablets whole with a drink of water. Do not break or crush them.

How long to take it for

You'll usually take finasteride for a long time. You may need to take it for several months or years.

Do not stop taking it without talking to your doctor first. If you stop taking it, your enlarged prostate symptoms or hair loss will usually come back.

If you forget to take it

If you miss a dose and it's less than 6 hours since you were due to take it, take your finasteride as soon as you remember.

If it's more than 6 hours since your dose was due, skip the missed dose and take the next one at the usual time.

Do not take 2 doses to make up for a forgotten dose.

If you forget doses often, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to help you remember to take your medicine.

If you take too much

Finasteride is generally very safe. Taking too much is unlikely to harm you.

you take more than your prescribed dose of finasteride and feel unwell

Go to 111 online or call 111

If you need to go to A&E, do not drive. Ask someone to drive you or call 999 and ask for an ambulance.

Bring the finasteride packet or leaflet inside it, any remaining medicine, and any other medicines you take.

Common side effects

These common side effects of finasteride happen in more than 1 in 100 people.

They usually improve after a while, but they can sometimes carry on even after you stop taking finasteride. There are things you can do to help cope with them:

Speak to your doctor if you get these side effects.

If the amount you ejaculate is less than usual or you have no semen at all, speak to your doctor.

Serious side effects are rare and happen in less than 1 in 1,000 people. Some people may notice these side effects after taking finasteride for a few months.

Call your doctor or call 111 now if you get:

any lumps, pain or swelling in your chest area or discharge from your nipples – these may be signs of a serious condition such as breast cancer
low mood (depression) – if you're taking it for hair loss and you get this side effect, stop taking the medicine straight away

It's important to tell your family or friends that you're taking finasteride, and that it may sometimes affect your mood or behaviour. This is so that they can help you notice any changes.

you have thoughts of harming yourself

Find your nearest A&E

Meds - serious side effects A&E safety messaging

In rare cases, finasteride may cause a serious allergic reaction (anaphylaxis).

Meds New IA (H4) - serious allergic reaction

These are not all the side effects of finasteride. For a full list see the leaflet inside your medicines packet.

Finasteride and pregnancy

Only very small amounts of finasteride are present in semen. If you're pregnant and your partner takes finasteride, it's very unlikely that this will cause any harm to you or your baby.

The manufacturers of finasteride still recommend using a condom when having sex, but the actual risk is unlikely to be significant. Most experts agree that this is not necessary.

Finasteride and male fertility

Some men taking finasteride have reported test results showing that they had poor sperm quality or were infertile. This is not a common side effect and your sperm usually returns to normal after you stop taking finasteride.

Sexual side effects

Finasteride can give you side effects such as not being able to get an erection (erectile dysfunction) and having less interest in sex (loss of libido).

If these side effects do not go away, are worrying you or are affecting your sex life, speak to your doctor.

Cautions with other medicines

Finasteride is not affected by other medicines.

Mixing finasteride with herbal remedies and supplements

St John's wort (a herbal remedy sometimes taken to help with depression) might stop finasteride working as well as it's supposed to.

There's not enough information to say that other complementary medicines, herbal remedies and supplements are safe to take with finasteride. They're not tested in the same way as pharmacy and prescription medicines. They're generally not tested for the effect they have on other medicines.

Meds New IA (H2) - Cautions with other medicines alert