Many people exposed to the Epstein-Barr virus do not show symptoms of the disease, but carry the virus and can transmit it to others. This is especially true in children, in whom infection seldom causes more than a very mild illness which often goes undiagnosed.

Ampicillin and amoxicillin should also be avoided, since they cause an allergic-like rash in 90% of mono patients.

I got a rash from amoxicillin as a kid. Let's hope that means i'm immune to mono.