Did you ever think that taking Propecia might one day save your life? A study in The Lancet Oncology found that in men aged 40 – 60 years, taking 1mg/day of finasteride for 48 weeks lowers serum PSA concentration. Within 48 weeks of randomization, men aged 40 – 49 years and 50 – 60 years who were assigned 1mg/day finasteride had a median decrease in serum PSA concentration of 40% and 50%, respectively.