Is it safe to take propecia (finasteride). I heard that it has serious side effects like impotence & erectile dysfunction?

Yes ; no. As w/all medications ; dietary supplements, there are side effects, whether acknowledged or not. Never believe any ad that claims there are no side effects just b/c it's natural, organic or herbal. With that said, never take any medication or dietary supplement unless you need it and benefit > risk. Propecia (finasteride) is fda approved brand of Finasteride w/known risk of side effects as noted but not guarant.