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Propecia (Finasteride) – Male Baldness


Propecia is a prescription only drug for men, used for the treatment of male pattern baldness. Propecia is a brand name used for the drug finasteride.

Finastride was first used under the brand name Proscar to treat benign prostatic hyperplasia (BHP), also known as an enlarged prostate. It was noticed that a side effect of taking Proscar was that some balding patients found their hair began to grow back.  After several years research and an adjustment in the dose of finasteride from 5mg to 1mg, this new use for finastride was marketed under the name Propecia as a treatment for male pattern baldness.

Male pattern baldness is caused by the male hormone Dihydrotestosterone (DHT).  DHT is converted from the hormone testosterone by an enzyme found in the hair follicles.  DHT affects men predisposed to male pattern baldness by causing the hair follicles to shrink, resulting in hair growing slower and thinner with the hair eventually not being able to grow at all. Propecia works by blocking the enzyme converting testosterone to DHT, thereby reducing the concentration of DHT acting on the hair follicles. This results in the prevention of hair loss with increased hair growth and hair thickness in most men using the drug.  Propecia only affects hair loss on the scalp resulting from male pattern baldness. It does not affect hair growth anywhere else on the body.

Clinical trials show noticeably improved hair growth after 3-6 months of taking 1mg of finastride with the maximum benefit seen after 1-2 years.  After taking this dose for 5 years men have 90% chance of having more or the same amount of hair they started with compared to 25% of men not taking 1mg of finasteride.

What precautions should be considered before taking Propecia?

Women or children should never take Propecia.  A woman who is, or believes she might be, pregnant must not handle broken or crushed Propecia tablets as finastride, the active ingredient in Propecia, can be absorbed through the skin. If a woman is exposed to finastride during pregnancy it can pose a risk to development of a male fetus, as it effects the production of the hormone DHT which is necessary for the normal development of male genitalia.  If a woman accidentally comes into contact with this medication from a broken or crushed tablet, wash the area immediately with soap and water.

Patients taking Propecia need to be aware that finasteride is excreted in semen so the use of a condom is strongly recommended if a sexual partner is pregnant or likely to become pregnant.

Inform the doctor considering your prescription of any allergies or allergic reaction you have had to similar medications, dutasteride (Avodart) and Poscar which are used to treat BPH in men with an enlarged prostate.

If you are due to have a blood test for prostate cancer, discuss this with your doctor before taking Propecia as it can affect the test result.

It is also important to inform your doctor of any other medication or supplements you are taking and if you have any of the following conditions: –

  • Liver disease, or abnormal liver enzyme tests
  • Prostate cancer
  • A bladder muscle disorder
  • If you are unable to urinate

Are there side effects to taking Propecia?

Finasteride, the active ingredient in Propecia, suppress the body’s level of the hormone DHT that has a major role in sexual development and sexuality.  It is therefore not surprising that the most common side effects are a decreased libido, erectile dysfunction and ejaculation disorder, most notably in younger men taking the drug.  In most cases, patients who have experienced these side effects found problems resolved once they stopped taking Propecia.  However, some found that normal function did not return for several months or years, while a small number found sexual function never returned to normal.

Infertility has been reported in men who took finasteride for a long time and had other risk factors that may affect fertility, although once they had stopped taking the drug fertility improved or returned to normal.

Although there have been no clinical trials specifically looking at the risk of prostate cancer in men taking Propecia, the drug does carry a warning.  Clinical trials carried over a 7-year period found there may be a very small risk of an aggressive type of prostate cancer in men taking a higher dose of finasteride (5mg).  The trials did, however, show that the number of men who developed prostate cancer was lower in men taking finasteride compared with those taking nothing.

There have been cases of patients treated with Propecia having experienced depressed moods, depression and, less frequently, suicidal thoughts.  If you experience any of these symptoms, stop taking Propecia and contact your GP for advice as soon as possible.

If you experience any changes in breast tissue such as lumps, pain, enlargement or nipple discharge make an appointment to see your GP as soon as possible.  Although the incidence of male breast cancer in clinical trials for 5 mg finasteride was not significant, incidents of male breast cancer have been reported.

If you show any symptoms of an allergic reaction, such as swelling of your lips, face, or lumps under your skin (hives), stop taking Propecia and contact your doctor immediately. In the case of a serious reaction effecting your ability to breath or swallow, this is a medical emergency, call an ambulance.

Other side effects to look out for are: –

  • Heart palpitations
  • Changes in liver function (will show up in a blood test)
  • Pain in the testicles
  • Persistent problems with sexual function and drive after discontinuation of treatment

If any of these side effects get serious, cause you concern or you experience any other side effects not listed here, speak to your doctor.

How to take Propecia

The recommended dose is one tablet taken at the same time each day, with or without food.

Propecia will not work faster or better if more than one tablet is taken each day and do not take a double dose if you forget to take it.  Take Propecia exactly as prescribed by your doctor.  If you take too many tablets, contact your GP immediately.  An overdose of Propecia is unlikely to be life threatening but it is best to seek advice as a precaution.

It can take 3-6 months before a noticeable improvement can be seen, however, if no improvement is seen after 12 months it is very unlikely that there will be any benefit in continuing treatment.

If you stop treatment you are likely to lose the hair you have gained within 9 to 12 months.

If you have been prescribed Propecia, please ensure you read the patient information in full before you begin taking this medication.