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.
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.
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 the highest suppression of DHT was achieved with 2.5mg or 5.0mg per day. At a daily dosage of 2.5mg or 5.0mg, Dutasteride suppresses close to 100% of DHT. This compares favourably with 5.0mg daily dosage of Propecia (Finasteride) which suppresses only 70% of DHT.
You should know, however, that Dutasteride is very effective at 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?
Clinical trials showed that it was generally well tolerated. Most side effects were mild, and generally went away while on treatment in both the Dutasteride and the placebo groups.
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:
- Dutasteride on Wikipedia
- Bernstein Medical - Dutasteride vs. Finasteride - A great article explaining the effectiveness of Dutasteride compared to Finasteride when used for combatting male pattern hair loss. It uses several clinical trials to derive it's conclusions.
- Comparison of clinical trials with Dutasteride and Finasteride
- Dutasteride Phase iii Results - The full results of the phase iii trials conducted by GlaxoSmithKline on Dutasteride for the treatment of Androgenetic Alopecia