I'm on tysabri(for ms and have had a cold for the past 3 weeks.penicillin, anti inflamitories, cold and flu tablets are not working.should i be worried?

Maybe not: Check with your regular doctor, may not be related to tysabri (natalizumab). The touch pharmacy as a "checklist" that we have to go through before you receive an infusion. If you are concerned, ask your regular doctor for help first. For example, nasty sinus infections can be hard to kick.

Infection risk inc.: Patients taking tysabri (natalizumab) are at an increased risk for infections. The most common were pneumonias, urinary tract infections , gastroenteritis, vaginal infections, tooth infections, tonsillitis, and herpes infections. Patients also usually have monthly blood work which will assess your white count. Please let your neurologist know so you can have a more thorough evaluation. Well wishes.

See your doctor: No need to worry, as this is NOT a sign of pending PML, but maybe a sign of bacterial infection which is resistant to penicillin (very common), and you need a different antibiotic to combat the problems. Nasal rinses will also help.