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Finasteride Guide: Uses, Results & Side Effects
Dr Mir Malkani
Medically reviewed by
Dr Mir Malkani
Updated on September 5, 2023

Finasteride is a drug used to treat male pattern baldness, also known as androgenetic alopecia. Both topical and oral versions are available, but oral tablets are by far the most popular.

In fact, Finasteride tablets are the most commonly prescribed hair loss drug worldwide, with more than 69% of surgeons reporting that they always or often prescribe Finasteride 1mg to treat male pattern baldness [1].

Finasteride is one of the most successful non-surgical treatments for male hair loss. If you’d like to learn more about Finasteride and how it can treat hair loss, check out our comprehensive guide below.

Table of Contents

What is Finasteride and how does it work?

Finasteride belongs to a group of drugs known as 5α-reductase inhibitors, or DHT blockers. 5α-reductase is an enzyme that converts testosterone to dihydrotestosterone (DHT). DHT blockers limit the amount of testosterone that gets converted.

DHT, or dihydrotestosterone, is a major cause of male pattern hair loss. It binds to androgen receptors in the hair follicles, causing the follicles to shrink. These miniaturised follicles eventually stop producing hair.

Finasteride works by reducing enzyme activity [2]. By stopping the enzymes from converting testosterone to DHT, there’s less DHT to bind to those androgen receptors. Over time, the affected hair follicles start to produce hair again.

Finasteride comes in two strengths: 1mg and 5mg. Finasteride 1mg is commonly found under the brand name Propecia, while 5mg is sold as Proscar. Propecia is suitable for pattern baldness, while Proscar is used to treat benign prostate enlargement (also known as benign prostatic hyperplasia) which is characterized as having symptoms associated with having an enlarged prostate gland. Individuals who suffer from benign prostatic hyperplasia often experience difficulties with urination.

Hair loss medication drug chart

Does Finasteride work?

Yes, Finasteride is effective as a hair loss drug. Many studies have proven its efficacy for blocking DHT production and stimulating hair growth:

  • Scalp DHT levels decreased by 64% after just 42 days of treatment [3]
  • 66% of men saw active growth in areas previously affected by hair loss [4]
  • Long-term improvements in hair growth, density, and hair loss prevention [5]
  • 87% of 2,561 men saw positive Finasteride results [6]
  • A 1999 study demonstrated that median scalp DHT levels decreased by 64% and 69% after 42 days of treatment at doses of 1 mg and 5 mg respectively. It also showed that even lower daily doses of Finasteride (>0.05mg) could significantly decrease scalp DHT [3].
  • A review of three Finasteride studies found that 48% of men had clear hair growth after one year of use, increasing to 66% after two years. This compared with just 7% of participants taking a placebo [4].
  • Two phase 3 trials involving 2,768 male participants found durable improvements in scalp hair over five years [5].
  • A five-year study involving 2,561 Japanese men found hair improvements in 87.1% of participants. Of these, 11.1% had great hair regrowth, 36.5% saw moderate regrowth, and 39.5% had slight regrowth [6].

As these studies show, Finasteride is a reliable hair loss treatment. It can prevent further hair loss and increase hair growth rates in many men who are suffering from androgenetic alopecia.

However, Finasteride must be taken continuously to see long-term effects. If you stop taking Finasteride, your DHT levels will return to normal and your hair loss will continue.

Does Finasteride work for facial hair?

Although Finasteride has some pretty impressive results when it comes to improving the hair on your head, it won’t have the same effect on your beard.

Facial hair isn’t sensitive to changes in DHT levels, so Finasteride is only approved for use as a scalp hair loss treatment.

If you’re struggling to grow a beard, or want to work on your facial hair, Minoxidil for beard growth may be a better option.

Will Finasteride work if I’m taking other medications?

There are no known drug interactions for Finasteride [7]. So you should be able to take Finasteride safely even if you take other medicines.

Finasteride can actually work better if it’s used alongside Minoxidil. Minoxidil is proven to help with hair loss, but it works in a different way than Finasteride. Instead of blocking DHT production, it opens up the blood vessels in the scalp, so more nutrients and oxygen can reach your follicles.

Combining these medications can give better results than just using Finasteride, with no additional risk [8].

Studies also show that using topical Minoxidil fortified with Finasteride can help maintain hair growth after a course of oral Finasteride [9].

How to apply topical Finasteride

Although many men favour oral Finasteride treatments, you can also get topical treatments.

Some people may prefer this option as it doesn’t come with the same side effects as topical Finasteride. However, it’s very unlikely for men to experience any serious negative side effects even when taking the treatment orally. Learn more about the difference between topical vs oral Finasteride.

To apply topical Finasteride:

  • Using a pipette or dropper, apply the solution directly to the balding areas of your scalp
  • There’s no need to rub it in
  • Apply up to 1ml to the scalp twice a day, leaving at least eight hours between applications

Oral Finasteride is still the most common method and can be combined with other medications to maximise results. Topical Finasteride is not as widely researched, although some studies have proved it can offer significant hair loss improvements without the systemic side effects of oral Finasteride [10].

Who can take Finasteride for hair loss?

Most men with male pattern baldness can take Finasteride. It’s not usually recommended for women and children.

Studies have shown that Finasteride 1mg doesn’t always create good results in female hair loss patients [11]. While it may be effective for certain women — particularly postmenopausal women with female pattern baldness — the risks generally outweigh the benefits, so women can’t normally take Finasteride.

Finasteride may also cause problems in pregnancy [12]. So it’s generally recommended that both women and men avoid Finasteride when trying to conceive. Women who are pregnant or plan to become pregnant soon are advised not to handle any broken finasteride tablets as exposure to the drug may result in birth defects in the unborn baby.

Finasteride may be used to treat transgender patients, but it’s not always suitable. Consult your doctor before starting a course of Finasteride.

Children and teenagers need higher levels of DHT for ongoing physical development, so blocking this hormone can be dangerous in young patients.

Finasteride is also generally ineffective for patients with other hair loss conditions, including:

Visit a reputable hair loss clinic or trichologist to find out if you’re eligible to use Finasteride.

Finasteride 'What to Expect' hair growth chart

How long does Finasteride take to work?

Finasteride is a proven hair loss treatment, but it’s not a miracle worker. So don’t expect to see drastic results overnight.

Here’s what you can expect to see at each stage of the Finasteride timeline:

Finasteride at 1-3 months

  • Your body stops converting as much testosterone to DHT immediately
  • Delayed reaction while the hair growth cycle catches up with your DHT levels
  • No visible hair regrowth or hair loss cessation
  • Increased Finasteride shedding

Finasteride at 3-6 months

  • Early results start to become visible
  • Hair loss slows considerably
  • Early signs of regrowth, especially on the crown

Finasteride at 6-9 months

  • Hair loss stops completely
  • Noticeable signs of hair regrowth
  • Fuller, denser hair across the crown

Finasteride at 9-12 months

  • Final results start to emerge
  • Should see a significant difference in hair density compared with pre-Finasteride use
  • Fuller, denser hair across the crown
  • Straighter, lower hairline if using Finasteride for a receding hairline

To stay aligned with this timeframe, you’ll need to take Finasteride once a day. If you decide to take Finasteride three times a week, your progress will probably be slower. Learn how long it takes for Finasteride to work.

What results can I expect from using Finasteride?

Your results will depend on how much hair you’ve already lost. Men at earlier stages of hair loss on the Norwood Scale will see more density than those who have already lost a lot of hair. So it’s a good idea to consider it as soon as you can see your scalp through your thinning hair.

These real patient Finasteride results show what this drug can achieve:

Finasteride effectiveness at baseline, 12 months, and 24 months.
Finasteride effectiveness at baseline, 12 months, and 24 months.
Finasteride results in a 25-year-old male patient.
Finasteride results in a 25-year-old male patient.
norwood 6 patient before and after finasteride
Patient before Finasteride treatment and after 6 months of taking 1mg per day.

How much does Finasteride cost?

Finasteride costs upwards of £12.20 for a month’s worth of 1mg Finasteride tablets.

Prices vary depending on:

Finasteride side effects: what are the risks of taking Finasteride?

Finasteride is generally safe to take on a daily basis. But there are some risks to taking the drug.

Some men who take Finasteride encounter side effects that can vary in severity. These side effects are rare but should be considered before you start taking Finasteride.

Some of the most commonly reported side effects of Finasteride include [13]:

  • Finasteride shedding
  • Erectile dysfunction (which affects approximately 1.3% of Finasteride users)
  • Decreased sex drive (1.8%)
  • Ejaculation disorder (1.2%)
  • Testicular discomfort
  • Skin rashes.

Less common side effects include Finasteride-related gynecomastia (swollen breast tissue in men) and lumps or pain around the breast area.

Finasteride can also pass into semen, so it shouldn’t be used if you’re trying to conceive. It may cause problems during pregnancy and harm an unborn baby. Use a condom if you’re sexually active and taking Finasteride. Learn more about Finasteride and fertility.

Most side effects will only last while you take Finasteride. As soon as you stop taking it, the side effects should stop. In very rare cases, post-Finasteride syndrome can occur.

There are also things you can do to manage these side effects. Taking Finasteride and Viagra may help with erectile dysfunction, while a dermatologist may be able to help you manage any skin concerns.

What is post-Finasteride syndrome?

Post-Finasteride syndrome occurs when you continue to experience Finasteride-related symptoms even after you stop taking the drug.

There’s some debate about whether post-Finasteride syndrome is a condition with genuine symptoms, or the product of a nocebo effect [14]. The syndrome is very rare, with one study estimating just 1,000 people have experienced it worldwide [15].

More conclusive research is needed to help doctors better understand this condition, and how it affects men with male pattern baldness.

The link between Finasteride use and cancer

Finasteride use has also been linked with male breast cancer and prostate cancer [13]. Breast cancer is more common in men taking a 5mg dose (50 cases up to 2009) than those taking a 1mg dose (three cases up to 2009) [16].

More research is needed to establish a clear link between Finasteride and breast cancer. But if you experience any of the following symptoms, talk to your doctor as soon as possible:

  • Breast lump(s)
  • Nipple discharge
  • Rashes on the breast or around the nipple
  • Any other changes to the nipple

The link between Finasteride and prostate cancer has been queried. A 2003 study suggested Finasteride could reduce the risk of low-grade prostate cancer, while increasing the chance of developing high-grade prostate cancer [17].

However, more recent evidence suggests there’s no correlation between Finasteride use and high-grade prostate cancer [18]. Instead, it’s thought that Finasteride alters PSA (prostate-specific antigen) levels which makes prostate cancer easier to detect [2].

That said, most men are at some risk of prostate cancer. So if you have any of the following symptoms, speak to your GP:

  • Needing to urinate more often
  • Difficulty urinating
  • Feeling you can’t fully empty your bladder
  • Blood in urine or semen

How to reduce Finasteride side effects

The only way to eliminate the risk of these side effects is to stop taking Finasteride. But this will limit your hair regrowth progress.

If you’re worried about Finasteride side effects, there are a few things that you can do to minimise the risk of experiencing side effects:

  • Take the recommended dosage — don’t try to speed up the process by taking more than is recommended or by taking a double dose after a missed dose
  • Take your usual dose of Finasteride at the same time every day — aim to leave 24 hours between each dose
  • Work out — physical activity can help with erectile dysfunction, so this is a good way to guard against sexual side effects [19]
  • Try topical Finasteride — topical solutions won’t have the same systemic side effects as oral Finasteride, although they may have their own side effects

If you follow these simple steps, you should notice significant improvements in your course of Finasteride. Your hair will grow back healthier and stronger, and you won’t have to worry about the range of side effects that some men experience while taking the drug.

What are some alternatives to Finasteride?

If you’re worried about or have experienced side effects, there are plenty of Finasteride alternatives to explore:

  • Minoxidil — a topical solution that stimulates blood flow to the follicles, triggering hair growth and helping to stop a receding hairline without affecting DHT levels
  • Dutasteride — an alternative DHT blocker that inhibits two types of 5α-reductase enzymes (note that Dutasteride may have similar side effects to Finasteride)
  • Natural DHT blockers — caffeine, rosemary oil, pumpkin seed oil, and black seed oil are natural remedies that have been linked with hair regrowth.

See our comparisons of Finasteride & Dutasteride and Finasteride vs Minoxidil to learn more.

Can I use Finasteride if I have a hair transplant?

Yes. In fact, you should use Finasteride after a hair transplant (or another preventative hair loss treatment).

Unlike a hair transplant, Finasteride prevents ongoing hair loss. So it’s important to manage the existing hairs around your hair grafts to keep your hair thick and full across the scalp.

The two most common forms of hair transplant are FUE (Follicular Unit Extraction) transplants, or FUT (Follicular Unit Transplantations). Both procedures provide natural and long-lasting results, and both are compatible with Finasteride.

We frequently recommend Finasteride to patients both before and after they have surgery to prevent any further hair loss. It’s one of the most recommended medications to take after a hair transplant, along with post-transplant Minoxidil.

Book a free consultation with the Wimpole Clinic

Get a private prescription for Finasteride from the Wimpole Clinic. We’ll assess your hair and scalp to make sure you’re eligible for Finasteride. If you’re not, or you want to try another solution, we’ll help you find the right solution to tackle your hair loss.

We offer all customers a no-obligation consultation where we take you through the process and can figure out if it’s the right approach for you.

Book a free consultation at the Wimpole Clinic to find out more.

Finasteride Guide: Uses, Results & Side Effects, Wimpole Clinic

Finasteride FAQs

Find out everything else you need to know about Finasteride in these FAQs.

Most men find a 1mg dose of Finasteride will give them the results they’re looking for.

In exceptional cases, your trichologist may recommend the 5mg dose. But this isn’t usually necessary and may put you at greater risk of side effects.

Finasteride tends to be less effective in women than in men. It may also cause problems during pregnancy, so women are generally recommended to avoid Finasteride.

No. Finasteride will only stimulate scalp hair growth, not facial hair.

You should take Finasteride for as long as you want to minimise hair loss. When you stop taking it, you may find your hair starts to thin again.

Dr Mir Malkani
Medically reviewed by Dr Mir MalkaniUpdated on September 5, 2023
The Wimpole Clinic offers FUE Hair, Beard & Eyebrow Transplants & Trichology.
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