Wow, please run as far away as humanly possible from your dermatologist. This is not a joke. He/she sounds like a complete wack. Unless your lips are actually infected by a bacterial infection that your immune system cannot handle, then its completely ridiculous to take Antibiotics "in case" they might get infected. Lymph node damage from peeling skin also sounds completely bogus. Taking anti-biotics for long periods of time can damage your system, get a second or third opinion from other dermatologists if you cant stop taking them on your own. Also, when you stop, look into supplements you should take after being on Antibiotics for so long. Probiotics is one I can think of. Also maybe take multi-vitamins to help your immune system too. Take care :)