Should i have my rat put to sleep or see if he gets better on the medication?

If he's still eating right now and not getting any worse, leave him be. I recently lost one of my girls last Saturday. She was two years old and got sick again, but this time she stopped eating (I tried getting her to eat and had her on meds and everything) and would either sleep or stay hunched over. She gave up on life after two weeks. :( If your little guy stops eating, take some action immediately. Try giving him some normally off-limits food that has a high fat content to bulk him up. :)