Propecia is the name of the drug Finasteride prescribed in 1mg doses to combat hair loss in men. Propecia side effects include some forms of sexual dysfunction which may alarm some users.

Just what is the evidence and are there any statistics to help us evaluate the risks involved with the side effects of Propecia?

The effects of Propecia and the side effects were noted on 1,553 males who took Propecia over a 2 year period.

Clinical trials produced the following statistics for Propecia side effects:

• Decrease in sexual desire: 1.8%
• Problems with erection: 1.3%
• Decrease in semen volume ejaculated: 1.2%

To put these figures into perspective, when monitoring Propecia's side effects, 3.8% experienced some kind of sexual dysfunction while 2.1% of the men using a placebo also experienced the same problems.

Additionally, these side effects were reversible in the men who discontinued taking Propecia and within some weeks they had disappeared.

One point to note is that the stopping of Propecia can result in losing any hair that has been regrown. The drug needs to be taken indefinitely to maintain the hair growth and density.

However, if a user discontinued taking the drug after experiencing the Propecia side effects noted above, it is very unlikely he would experience any decrease in hair growth. This is because it takes between three to six months of daily use to see any increase in hair growth and the side effects are experienced well before then.

As Propecia effects hormone levels some men experienced tenderness in the breast. However, this was a small number and no more than those who used the placebo.

Another aspect of Propecia side effects has to do with the detection of prostate cancer. The drug Finasteride which is contained in the Propecia tablets was originally marketed to combat prostate cancer in men over 50. It was prescribed in 5 mg doses.

Finasteride can affect a man's PSA levels (prostate specific antigen) which is often used as a screening test for prostate cancer. The use of Propecia may therefore affect the detection of prostate cancer. It has yet to be confirmed whether prolonged use of Propecia can actually reduce the risk of prostate cancer.

While the figures given above may not seem significant and in view of the fact these Propecia side effects are reversible if the drug is discontinued it may appear that there is little cause for concern.

However, another aspect should be noted. Even though a drug may receive FDA approval after rigorous tests and many years of clinical trials and reports, FDA approval does not mean the long term effects of a drug are known.

This perhaps is the most worrying aspect about Propecia's side effects. The fact that young men often take this drug for male pattern baldness and maintaining their level of hair growth is dependent on taking the drug, it means that a man will be using this medication perhaps for decades.

Just what are the side effects of Propecia after decades of use? Since it was only approved in 1998 no one can say.

In conclusion: While Propecia side effects may seem almost inconsequential from the information currently available, a young man who uses it for life may have to deal with more serious consequences in the future.