Goofy book about a kid who takes a series of experimental medicine and has strange side effects

May have been titled Side Effect?

It’s about a kid who has a condition so has to take drugs but they give him side effects like growing gills so he needs to where a fish bowl or something. Also goes swimming in the ocean to breathe under water.

Then he takes more experimental drugs to cure that but ends up with different side effects. You see where this is going.

Rented it from a library maybe 10 years ago.

I can’t remember the title or author. I know this is a long shot!