Does Propecia Strenghen Miniaturized Hairs Or Grow New Ones?

If Propecia gives you regrowth, will it first shed out the miniturized hairs and then grow healthy hairs or make the miniturized hairs just normal again?

Propecia increases the diameter of the hair shafts that are miniaturized, and one tends to see the most beneficial response in those hairs that are recently miniaturized. Some people see shedding after starting Propecia, and that could be due to speeding up the hair cycle so new, healthy hair grows. That’s just an educated guess shared by many doctors at this point, and not something that has been proven (as far as I’m aware).