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What is Dutasteride (Avodart)?

Dutasteride (brand name Avodart) is manufactured and marketed by GlaxoSmithKline. It is an active agent in an oral medicine, that has proved to be very effective in treating genetic male pattern hair loss on the top of the head and the mid-scalp area.

The medicine has been approved for prescription by the US Food & Drug Administration and in Europe for the treatment of benign prostatic hyperplasia (BPH). In addition, it is prescribed for the treatment of male pattern baldness (MPB) off label.

It is also known by its European brand name, Avolve.

Why was Dutasteride formulated?

Dutasteride was produced for treating symptomatic benign prostatic hyperplasia (BPH) in men. It is chemically similar to Finasteride - the active compound in Propecia, although it has proven to be more effective in clinical trials. Like Propecia, Dutasteride has proved to be effective in treating male pattern hair loss as well as BPH.

Graph showing comparison of DHT suppression in patients using Dutasteride compared with those using Finasteride.

How does Dutasteride work?

Scientific Researchers have discovered that men who suffer from either male pattern hair loss or benign prostatic hyperplasia (BPH), have an increased level of the hormone known as dihydrotestosterone (DHT).

DHT is produced from testosterone by an enzyme called 5-alpha-reductase. Biochemical analysis reveals that there is a higher levelnof 5-alpha-reductase in the bloodstream of men with BPH, and in the scalps of men with hair loss. Analysis also shows that there is less of this enzyme in men with no BPH or no hair loss.

Dutasteride works by inhibiting the 5-alpha-reductase, therefore blocking the formation of DHT, which interrupts a key trigger element in the development of male pattern hair loss and in the development of BPH.

How is Dutasteride different from Propecia?

Both medicines work in the same way, however, Dutasteride inhibits the activities of two types of 5-alpha-reductase enzymes, Type I and Type II. In contrast, Propecia (Finasteride) only inhibits one type, Type II . Dutasteride has been shown to decrease levels of DHT by 90% after only two weeks. This makes it a more powerful and faster-acting weapon against hair loss and BPH than Finasteride.

picture showing dihydrotestosterone (dht) effects on identical twins hair loss Above you can see the difference in hair count between me (right) and my twin brother (left). My twin has been using Dutasteride since late 2004 to block DHT from forming in his scalp; I only started using it in January 2010 - more photos.

What is dihydrotesterone (DHT)?

DHT is one of several male hormones in the body. It is responsible for the development of the external genitals in the male foetus. Nevertheless, in adult males DHT seems to cause:

  • male pattern hair loss
  • prostate enlargement
  • shortening of the growing phase of hair
  • progressive miniaturisation of hair follicles
  • decreasing number of visible hairs
  • acne

What research trials have been done regarding Dutasteride?

GlaxoSmithKline have completed Phase II trials for FDA approval of Dutasteride for the treatment of hair loss. After six month of treatment during phase II, the hair counts that were measured in a 1 inch diameter circle increased by an average of 96 hairs with the intake of 0.5mg Dutasteride, compared to an average of 72 hairs with the intake of 5mg Propecia (Finasteride). The drug was shown to be well tolerated.

Also, a total of 2951 men with moderate to severe BPH were treated with 0.5 mg Dutasteride daily. The study found that acute urinary retention was reduced by 57%, and the risk of benign prostatic hyperplasia-related surgical intervention was cut by 48% compared with the placebo. The drug was shown to be well tolerated.

So these trials show that Dutasteride is around 30% more effective than Propecia in promoting hair regrowth. However, please note that Dutasteride has only been specifically approved for treating BPH. It has not yet been approved specifically for treating hair loss.

When will Dutasteride be approved for treating hair loss?

It has not been approved for treating hair loss in the UK however; it is already approved by the US FDA and by European bodies for the treatment of BPH, and so it has already passed all the relevant safety standards.

Will Dutasteride help hair re-growth for all men?

As with Propecia, Dutasteride increases the number of scalp hairs, helping to fill-in thin areas of the scalp. Although results will vary, generally men will not re-grow all of the hair they have lost. Male pattern hair loss occurs gradually over time, but Dutasteride can significantly reduce or delay this process.

How should I take Dutasteride?

Dutasteride is supplied as a gel-filled capsules with 0.5mg dosage (GSK's Avodart). Take dutasteride exactly as directed by your doctor. If you do not understand these instructions, ask your pharmacist or doctor to explain them to you.

Take each dose with a full glass of water, and swallow the whole capsule. Do not chew, crush or break the capsules. Dutasteride can be taken with or without food.

What dosage should I take?

You should only take the dose as recommended by your doctor. Do not change the dose without consulting your doctor.

Effectiveness of Dutasteride has been evaluated at different daily dosages, ranging from 0.01mg, 0.05mg, 0.5mg, 2.5mg, and 5.0mg per day. It was found that by using 0.5mg per day of Dutasteride patients achieved a significant reduction in DHT concentration compared to those using 5mg of Finasteride. In non-comparative clinical trials, chronic therapy with dutasteride (0.5 mg daily) for up to 2 years in patients with BPH resulted in median reductions in serum DHT of 93%.4. In contrast, therapy with finasteride (5 mg daily) suppressed serum DHT concentrations by approximately 70% for up to 4 years in patients with BPH. Please consult the results here.

Dutasteride is very effective in small doses. DHT inhibition is close to 90% at a daily dose of 0.5mg, In addition, the level of DHT suppression is not significantly greater between 2.5mg and 5.0 mg.

Is Dutasteride safe?

We personally cannot recommend Dutasteride for any treatment let a lone hair loss as we are not medically qualified to do so - nor do we wish to. We advise you consult your doctor about any sort of drug treatment for male pattern hair loss - they are the only people qualified to give you advice. The Clinical trials did show that Dutasteride was generally well tolerated by the test group. Most side effects were mild, and generally went away while on treatment in both the Dutasteride and the placebo groups. However this does not in any way offer you a guarantee that you will not experience side effects, we personally would recommend you consult your doctor before you decide on any course of treatment. Our site only serves as to highlight our personal circumstances and the medical information currently available on Dutasteride. Please also bear in mind that new tests and changes with regards to the supply of Dutasteride may occur beyond the scope of this article so we advise you do more research beyond our website. We do ensure we provide official references to all the information we use on our website.

Drug-related side effects during the first six months were as follows:

  • impotence (4.7% vs. 1.7% for placebo)
  • decreased libido (3% vs. 1.4%)
  • breast tenderness and breast enlargement (gynecomastia; 0.5% vs. 0.2%)
  • ejaculation disorders (1.4% vs. 0.5%).

Dutasteride should not be used in women and children. Women who are pregnant or may become pregnant should not handle this medicine because of possibility of absorption and subsequent potential risk to a male foetus.

Men treated with Dutasteride should not donate blood until at least six months after their final dose to prevent the medicine going to a pregnant woman through a blood transfusion.

Men with liver disease should talk to their doctor before taking Dutasteride.

For more information on Dutasteride please consult the following external links: