should I use PropeciaFfinasteride after hair transplant due to shock loss on recipient and donor?

It
is the shock loss on the recipient area that you should be concerned about
after a hair transplant.  However, you
should start finasteride to keep your native scalp hair but only after seeing a
specialist who can map your miniaturization of scalp hair.  The hairs you have in the donor area are
considered permanent hair and are coming from the permanent zone. These hairs
are not susceptible to Dihydrotestosterone (DHT) the hormone responsible for
hair loss in androgenetic alopecia.

In my opinion, the reason to add finasteride is not for any short term benefit this soon after your FUT procedure.  Your apparent telogen effluvium post-operative shedding, should start resolving soon. Finasteride side effects are quite unusual, but taking a prescription medication indefinitely is not a comfortable decision for many young men, especially when it may affect them sexually. It is a long term approach & very effective, but may not show any substantial benefit for nearly a year in many of my patients. I hope this is helpful. Waiting for the results after HT is difficult, but almost always worth the wait for the patient.  Try to relax & continue the LLLT.  You should be close to turning the corner with obvious benefit you can actually see by about 4-6 months in the typical patient.