係勁D
但半衰期長D
finasteride 減70% D血清HT
dutasteride減99%
Research has shown that finasteride reduces prostatic DHT levels by upwards of 90% and serum DHT levels by 70%. However, increasing the dose does not necessarily result in greater serum DHT reduction. Dutasteride, in contrast, inhibits all 3 5-alpha reductase isoenzymes, leading to a 99% reduction in serum DHT levels.
In treating androgenic alopecia, finasteride does not lead to a 100% reduction in DHT; hair loss is slowed but not completely halted. Patients receiving treatment for androgenic alopecia have a reversal of hair count within 12 months.[8]
In treating benign prostate hyperplasia, long-term use of finasteride has been associated with a reduction in prostatic volume, thereby relieving bothersome urinary symptoms attributed to an enlarged gland. Previously published literature has demonstrated a reduced risk of urinary retention and delayed the need for surgical intervention. Upon discontinuation of finasteride, DHT levels return to normal within 14 days.
https://www.ncbi.nlm.nih.gov/books/NBK513329/