Er doc says my ankle has severe cellulitis- after iv drip of antibiotics i'm sent home with more antibiotics - is very swollen how long i'm better?

Cellulitis: Be sure to take the full course of antibiotics prescribed. You should see some improvement in 48 hours with resolution in a week. Keep the foot elevated at or above the level of your heart to reduce swelling. If you see a red streak going up your leg from the ankle , go back to the ER. That is a sign of serve spread of the infection into the lymph system.

Typically cellulitis: is only on one leg. so if that is the case and this is true cellulitis, antibiotics should help over next 2 weeks. Keep off leg, keep it elevated. If not much better in 2 weeks get in to see dermatologist

Depends: If you don't have any medical conditions that could slow down your recovery, you should start seeing improvement in the next 48 hours or so and complete improvement in about a week or so. You will need to complete your antibiotics course even if you have take them longer than a week. Follow up with your PCP in the next few days to make sure you're improving.