How long does it take to lose loose skin when you have a lot of weight loss?

Depends: When you lose weight, your skin should shrink with you... It shouldn't lag behind your weight loss. If after losing your weight you have a significant amount of loose skin, you will likely need some form of skin tightening procedure depending on which areas are bothering you.

Depends: It depends on the amount of weight loss and the age of the person. The most favorable results are in the young due to increased skin elasticity and in those with minor weight loss. If it is going to retract, should take less than a year. Massive weight loss often results in skin excess that will have to be surgically excised.