I am worried to take Finasteride because I have read that becoming impotent is a possible side effect. Is this true?

Impotence is an uncommon side effect of finasteride. The most recent data indicate that 1-2% of male patients may experience this.  This is usually a temporary situation as the body becomes accustomed to the medication.  It's also important to realize that erectile dysfunction is caused by and related to many factors, so sometimes patients may have other issues going on.  It's useful to discuss the pros and cons of any medication with a qualified medical provider.

Yes, it is possible although the risk is quite low. Less than 2 % of males experience sexual dysfunction, including impotence, while using finasteride. There is no good way yet to predict.