I'd love to see a picture of your medallion.  Kyle (17) and Erin (14) both have medic alert medallions and hate them.  I find that Kyle takes his off all the time.  Erin wasn't allowed to wear it during volleyball games.  Off it came, down in gym bag it went, and it didn't come out until I mentioned it again.  The chain is too long, and the medallion is too big.  Erin might wear a bracelet but Kyle won't.