All antibiotics can have problems with any portion of the general population. I have used sulfa drugs for years then became allergic. Levaquin was used by me a couple of times then it almost destroyed my Achilles tendons.

It is not unusual that drugs end up on a caution list for MG just because there are a couple (or even one) bad reactions with MG patients. They may have reacted anyway, with or without MG. For the most part, drug caution lists are not based on controlled studies. They are largely anecdotal in nature.

Bill