The Independent Pharmacy

Finasteride (Propecia) vs. Dutasteride - Which Is Better For Hair Loss

Daniel Hurley
Daniel HurleyMPharm IPPharmacist Independent Prescriber

Reviewed on 11 Oct 2024

Hair loss, a deeply personal and often distressing experience for many men, can profoundly impact self-esteem and confidence.

For many grappling with hair loss, finasteride (Propecia) and dutasteride have emerged as two comforting medical treatment options. Both belong to a class of medications called 5-alpha reductase inhibitors, which simply means that they work in a similar way to treat hair loss. But while finasteride has been approved and available on a private prescription as a hair loss treatment in the UK, dutasteride is not currently licensed for this purpose in the country.

Despite the shared similarities, there are important differences between finasteride and dutasteride that men should understand - from their side effects to the different recommended dosages.

Understanding all the big and small nuances between the two treatment options could define your overall experience and success on your journey.

Let’s see how Finasteride (Propecia) and Dutasteride compare.

Finasteride (Propecia) vs. Dutasteride at a Glance

Feature/AspectFinasteride (Propecia)Dutasteride
How They WorkBlocks a specific enzyme
to prevent hair loss.
Blocks two different enzymes
for more effective hair
loss prevention.
Effectiveness in
Hair Loss
Helps most men slow
down or even reverse
hair loss.
Generally more effective than
Finasteride in regrowing hair.
Dosage1 mg once daily.0.5 mg once daily.
FormComes as a tablet.Comes as a capsule.
Time to See
Results
Results can be seen
in up to 3-6 months.
Results can be seen between
3 to 6 months.
Common Side
Effects
May include reduced
sexual drive, mood changes,
and skin reactions among others.
May include reduced sexual drive,
mood changes, and allergic reactions.
Who Shouldn't Take ItPregnant women, children,
those allergic to it, and those
with certain medical issues.
Pregnant women, children,
those allergic to it, and those
with liver issues.
Duration for
Effectiveness
Needs to be taken long-term
for maintaining results.
Also requires long-term use for
best results.
Upon Stopping the
Medication
Hair loss may return
within 6-12 months.
Hair loss can come back within
6-12 months.


Finasteride (Propecia) vs Dutasteride - Detailed Comparison

How They Work

Finasteride (Propecia)

Finasteride, also available in a branded form of Propecia, works by blocking 5-alpha reductase enzymes. This enzyme changes testosterone, a male hormone, into another hormone called DHT, which can cause hair loss. When levels of DHT are too high, it can cause hair follicles to shrink and stop producing hair. Finasteride stops the conversion process by blocking this enzyme, so testosterone doesn’t get turned into DHT as much. This helps hair follicles return to normal and stimulates new hair growth.

Dutasteride

Dutasteride works in a similar way to finasteride. It blocks the enzyme 5-alpha reductase so testosterone doesn’t get converted into DHT as often. The main difference is that dutasteride works on two versions of this enzyme, while finasteride works on just one. Blocking both types is thought to make dutasteride more effective in treating hair loss. This medication lowers DHT levels, removes the suppression of hair follicles, and encourages new hair growth.

Uses of Both Medications

Finasteride (Propecia)

Finasteride is one of the rays of hope for those experiencing male pattern hair loss or baldness. It stops further hair loss and helps regrow hair.

At higher dosages, finasteride is also used to treat an enlarged prostate, which can cause problems like slow urine flow and the need to urinate often. Finasteride helps shrink the enlarged prostate to relieve these symptoms.

Dutasteride

Like finasteride, dutasteride is primarily used for treating hair loss in men. It effectively slows down hair loss and stimulates new hair growth.

Dutasteride is also used for treating prostate enlargement. It works to shrink the enlarged prostate gland. This helps improve urine flow and urinary symptoms that come from having an enlarged prostate. Dutasteride provides faster relief of these symptoms compared to finasteride.

Effectiveness in Treating Hair Loss

Finasteride (Propecia)

Studies have found finasteride works well to slow down and possibly reverse hair loss for most men. In research trials, after taking finasteride for 5 years, over 80% of men had stabilised or improved their hair loss.

It’s important to note that many men begin to see positive changes within 3-6 months of starting treatment. It’s essential to continue taking finasteride to maintain these results. We understand the commitment involved, and it’s worth noting that discontinuing can lead to a return of hair loss.

Dutasteride

Research shows dutasteride is more effective than finasteride for treating male pattern baldness. Studies directly comparing the drugs show that dutasteride regrew more hair than finasteride after 6 and 12 months of treatment.

One study found that dutasteride helped regrow over 100 hairs in a small area (about the size of a postage stamp) in 24 weeks. Finasteride only regrew about 60 hairs in the same time period. Dutasteride works better because it blocks two enzymes involved in hair loss rather than just one.


Dosage and Administration

Finasteride (Propecia)

The recommended finasteride dosage for hair loss is 1 mg taken orally once daily. It comes in tablet form. Finasteride works best when taken consistently every day. The full effects may take up to 3-6 months. It can be taken with or without food.

Pregnant women, or women who might become pregnant, shouldn’t touch finasteride because it can harm the baby. Tablets should be kept away from children.

Dutasteride

The standard dosage of dutasteride for treating hair loss is 0.5 mg, taken orally once a day. It comes in a soft gelatin capsule that should be swallowed whole. For maximum benefit, it needs to be taken consistently daily. It may take 3-6 months to see the full effects. Dutasteride can be taken with or without food.

Like with finasteride, pregnant women and children shouldn’t touch dutasteride capsules because they can be harmful if absorbed through the skin. They should be stored safely out of reach.


Common Side Effects

Finasteride (Propecia)

Finasteride is generally well tolerated, but possible adverse effects may include:

  • Sexual side effects include decreased libido, erectile dysfunction, and reduced ejaculate. These occur in less than 2% of men and are reversible.
  • Enlarged breasts or breast tenderness. This affects less than 1% of men using finasteride.
  • Skin rash or allergic reaction.
  • Swelling of lips, tongue, throat or face.
  • Depression, anxiety and other mood changes.

In very rare cases, finasteride may cause male breast cancer. It does not appear to increase prostate cancer risk.

Side effects typically resolve after stopping treatment. Discuss concerns with your doctor.

Dutasteride

Potential side effects of dutasteride include:

  • Decreased sex drive, sexual dysfunction, or problems with ejaculation. These are uncommon but can persist even after stopping the medication.
  • Enlarged breasts or breast tenderness. This affects less than 1% of men on dutasteride.
  • Allergic reactions like rash, itching or swelling. Very rare but serious.
  • There’s a small chance it could lead to a more severe type of prostate cancer.
  • Mood changes like depression or anxiety.

Dutasteride might not work well with some other medicines, like those that prevent blood clots.


Who Shouldn’t Take the Medication

Finasteride (Propecia)

Finasteride should not be taken by:

  • Women who are pregnant or may become pregnant. It may cause birth defects in a male baby.
  • Children or teenagers under 18 years old.
  • Anyone with liver disease or impaired liver function.
  • People who have had an allergic reaction to finasteride or any of its ingredients.

Before starting finasteride, let your doctor know if you have any other medical conditions. Use caution if you have a history of depression or prostate cancer.

Dutasteride

People who should not take dutasteride include:

  • Women who are or may become pregnant. Dutasteride may harm a developing male fetus.
  • Children under age 18.
  • Anyone with severe liver impairment.
  • Individuals with known allergy to dutasteride, other 5-alpha reductase inhibitors, or ingredients.

Inform your doctor if you have prostate cancer, liver disease, or depression before starting dutasteride. Use caution if taking blood thinners or medications for an enlarged prostate.


Duration and Commitment

Finasteride (Propecia)

Finasteride is effective only if taken consistently long-term. It may take 3-6 months to see results, and continued treatment is necessary to maintain benefits. Hair loss will resume about 6-12 months after stopping finasteride.

Some men use finasteride indefinitely to preserve existing hair. Others discontinue use after 2-5 years once desired results are achieved. Lifelong treatment may be an option for some men if the benefits continue to outweigh the risks.

Discuss the expected duration and long-term plan with your doctor. Do not stop taking finasteride without guidance.

Dutasteride

Like finasteride, dutasteride requires long-term use to maintain results. Maximum increase in hair count may take 3-6 months, then continued treatment is needed. Hair loss is likely to return 6-12 months after stopping dutasteride.

Some men may take dutasteride long-term to preserve hair. Others may discontinue use after 2-5 years once satisfied with hair growth. Ongoing treatment for hair loss may be appropriate if the benefits continue to outweigh the potential side effects.

Talk to your doctor about the expected timeframe and long-term administration plan for dutasteride. Do not stop treatment abruptly without medical supervision.


Stopping the Medication

Finasteride (Propecia)

If you stop taking finasteride, the effects will wear off over time. DHT levels will rise again, leading to renewed hair loss about 6-12 months after discontinuation.

Some men may experience a temporary shedding period of about 2-3 weeks after stopping finasteride. This is normal and reflects hair follicles starting to shrink again.

It’s possible to restart finasteride treatment after discontinuation. The medication can be effective again, but repeat commitment to daily use is required to maintain benefits. Do not stop finasteride without consulting your doctor first.

Dutasteride

When dutasteride treatment is stopped, DHT levels will gradually increase again. This will result in renewed hair loss around 6-12 months after discontinuation.

Some temporary shedding may occur in the first few weeks after quitting dutasteride. This reflects the reversal of its positive effects on hair follicles.

It is possible to restart dutasteride after stopping and have it work again. However, consistent long-term administration is needed to maintain regrowth. Do not stop dutasteride without medical guidance.


Special Considerations

Finasteride (Propecia)

  • Finasteride takes up to 3-6 months for full effect. Be patient and do not increase dosage without medical advice.
  • If you’re sexually active while taking finasteride, use barrier contraception like condoms. Inform partner about potential risks.
  • Avoid giving blood while on finasteride, and wait at least a month after stopping before you do.
  • Inform your doctor about all medications and supplements you take. Be cautious of interactions.
  • Get regular checkups to monitor progress and undergo PSA testing if recommended.

Dutasteride

  • Allow 3-6 months for dutasteride to work. Do not increase the dose without consulting your doctor first.
  • Use condoms or other barrier methods if sexually active during treatment. Avoid contact with pregnant partners.
  • Do not donate blood during dutasteride treatment or for 6 months after discontinuing.
  • Tell your doctor about all medications, vitamins and supplements you take to check for interactions.
  • See your doctor regularly for checkups and recommended screening tests like PSA.


The Overall Verdict

In summary, both finasteride and dutasteride can be effective medical treatments for hair loss in men. While the drugs share similarities, dutasteride appears more potent, leading to faster results and greater hair regrowth. However, it may also have a higher risk of sexual side effects that persist after stopping treatment.

At The Independent Pharmacy, we understand that choosing a treatment is deeply personal and depends on various factors, from the extent of hair loss to individual experiences with side effects and personal circumstances. We’re here to guide you through these considerations. For some men, choosing dutasteride as a first-line treatment makes sense to stop hair loss progression quickly. For others, starting with finasteride may be preferable to minimise risks.

We encourage you to have an open conversation with your doctor, sharing your feelings and concerns, to determine whether finasteride or dutasteride aligns with your unique needs. Ask about expected results, potential side effects, and required commitment. Work together to make an informed decision on the hair loss treatment plan right for you. Consistency and patience are key to the best results from these medications.

FAQs

Is dutasteride better than finasteride?

Research shows dutasteride grows more hair than finasteride. But it also has a higher chance of sexual side effects that can last after stopping the medication.

Is dutasteride the best for hair loss?

Dutasteride is one of the most effective medications for treating male pattern baldness. However, it may not be the best option for every person.

Is dutasteride worth the risk?

Dutasteride works very well for hair loss but can cause sexual side effects. Talk to your doctor to see if it is worth the risks for you.

Will dutasteride work if finasteride didn’t?

In some cases, dutasteride may regrow hair when finasteride did not. This is because it works in an additional way. However, results vary and are not guaranteed.

Finasteride vs Dutasteride: The Choice Is Yours

Facing hair loss can be an emotional and challenging journey. Finasteride and dutasteride provide effective treatment options that may help regrow hair. Deciding which drug is better for your needs requires careful evaluation.

Talk to your doctor to understand the differences between these medications. Ask questions to weigh the potential benefits and side effects. Discuss your health, lifestyle, priorities and commitment to long-term treatment.

Consider starting with finasteride to minimise risks if you have concerns. However, dutasteride may provide faster, superior hair regrowth for those seeking robust results. Consistency is vital to achieve the best outcomes with either drug.

We know it’s tough, but patience is key. It takes time to see the full benefits, and we’re here to support you every step of the way. Always take these medicines as directed by a doctor. We recognise the courage it takes to address hair loss. Armed with the right information and a proactive mindset, treatments like finasteride or dutasteride can offer a beacon of hope in your journey.

Sources:

About finasteride - NHS (www.nhs.uk)

Dihydrotestosterone - South Tees Hospitals NHS Foundation Trust

Benign prostate enlargement - NHS (www.nhs.uk)

Evaluation of long‐term efficacy of finasteride in Korean men with androgenetic alopecia using the basic and specific classification system - PMC (nih.gov)

A randomized, active- and placebo-controlled study of the efficacy and safety of different doses of dutasteride versus placebo and finasteride in the treatment of male subjects with androgenetic alopecia - PubMed (nih.gov)

Dutasteride | Drugs | BNF | NICE

Finasteride and sexual side effects - PMC (nih.gov)

Dutasteride: A Review of Current Data on a Novel Dual Inhibitor of 5α Reductase - PMC (nih.gov)

Post-finasteride syndrome - PMC (nih.gov)

Persistent Erectile Dysfunction after Discontinuation of 5-Alpha Reductase Inhibitor Therapy in Rats Depending on the Duration of Treatment - PMC (nih.gov)

Prostate cancer - PSA testing - NHS (www.nhs.uk)

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