community From the research study: "Dihydrotestosterone and the concept of 5a-reductase inhibition in human benign prostatic hyperplasia" - G. Bartsch, R.S. Rittmaster, H. Klocker (2002) in the "World Journal of Urology".
Dutasteride is a stronger 5AR inhibitor than finasteride and can significantly lower DHT levels. Reduced doses of dutasteride may lower side effects.