I'm 18 & a male! i lost 45 pounds from dieting. now my skin is extremely saggy. it's been 2 months since i've lost this weight, how do i fix the saggy?

Saggy skin: If the skin hasn't contracted in two months, then likely you will need to have the loose skin excised. My guess is that the sagging skin is in your abdomen, so you will need an abdominoplasty (tummy tuck).

Wait a while: At 18, the skin has excellent capacity to retract, and a 45 pound weight loss is not excessively large. You may be surprised at how much skin shrinkage there is over the next 4-6 months. I don't think you are losing anything by waiting a while. Even if you need the skin operatively removed, the operation may be smaller if you wait.

Give your self time: If it has been only 2 months since your weight loss, i would give it more time. You are young and you should do what is healthy for you. Continue on achieving your goals. If the loose skin does not improve after 6 months, speak to a plastic surgeon.