Drugs - finasteride

I am 31 years old and I am suffering from hair fall. I visited a clinic recently after diagnosis of my hair the doctor said it is MPT. Though my dad is 59 he still has hair. Since I am not completely bald I was advised by doctor to use Minoxidil twice a day and take a medicine which is Indian version of propecia which has 1% of Finasteride in it. I wish to know if this drug causes impotence or decrease in libido. In case one experiences any of the above will it be reversed once the medication is stopped.