I belong to an email group of hair transplant physicians who communicate regularly to share information. Most recently, the group was polled to determine the side effects that these doctors see with finasteride.
Most doctors reported sexual side effects (range from 2-5%), breast enlargement (very rarely, seems like substantially less than 1%), reduction in ejaculate volume (substantially less than the 20% I have seen when I ask about it), bouts of testicular pain (rare), and mood swings (rare). All side effects have been reversed by stopping the medication in 100% of the experience of these doctors.
This was an informal survey, but the general numbers seem to be similar to the instance of side effects reported by Merck. If someone in our group hopefully formalizes this possibly in a publication, I will post the results.
Many of our questions posted on BaldingBlog relate to Propecia/finasteride issues, which we point out may reflect the panic of some posters on the internet. Those in panic mode or those who are very fearful do not reflect the majority of men taking this drug.


I do not believe 11 weeks in and of itself should have a detrimental effect on your hair loss issue.
Propecia (finasteride 1mg) lasts about one day in your body. The half life (the time it takes for half of the medication to be cleared by your body) of Propecia is about 4 to 6 hours. Some have said there are still traces of Propecia that are left that can linger for about one week in general, thus the side effects should be dissipated by one week timeframe.
You can put styling products (pomade) to make your hair “feel” thicker. Medically, you can take Propecia (finasteride) to thicken the shaft size, but it is not a permanent solution. Herbal products and shampoos that claim hair thickening may accomplish this by adding water to the hair shaft. There is no scientific proof that Low Level Light Therapy (LLLT lasers) work in my experience.
In the U.S. generic finasteride is only legally sold in a 5mg dose due to patent laws, so the pill must be cut into pieces to get close to the proper dosing found in the 1mg Propecia. Aside from the difference in size (1mg to 5mg), generic finasteride has the exact same active medication as Propecia. Changing to brand name Propecia will likely not solve your son’s hair loss issue. It just may be that your son has genetic male pattern baldness (MPB) and it is running its course. Remember that there is no cure for MPB, and medication only goes so far. Having a