Propecia Side Effects vs Avodart Side Effects

1.If I use PROPECIA and report side effects, will the side effects occur with another 5AR inhibitor e.g. DUTASTERIDE?
2.Finasteride inhibits the enzyme 5AR.So we will have more testosterone in our blood. Why can sexual side effects occur?

Thank you for your time.

1. If you have any side effects associated with finasteride (Propecia), you will likely have side effects with dutasteride (Avodart). Dutasteride has the same mechanism of action as finasteride, but it blocks 5 alpha reductase type 1 and type 2 isoenzyme. Finasteride only blocks the type 1 isoenzyme. Please note that blocking type 1 and type 2 isoenzyme does not necessarily mean it will work better. More importantly, dutasteride is not recommended (nor approved by the FDA) for use in Male Pattern Baldness (MPB).
2. Finasteride blocks 5 alpha reductase, which is an enzyme that converts Testosterone t0 Dihydrotestosterone (DHT). DHT is the hormone that has been linked with MPB. When taking finasteride there is a transient effect of more testosterone, but it is only temporary because your body has other ways of metabolizing the temporary increase in testosterone. Sometimes there may be sexual side effects (1 in 10 increase in sex drive or 1 in 100 decrease in sex drive), because testosterone is a hormone responsible for sexual drive (and many other normal body fuctions).