each person reacts to concerta differently. that being said, it is a stimulant, and when taking stimulants it may increase heart rate, which in turn will decrease your immune system, thus making you susceptible to any form of sickness and diseases.
only explanation you can get for the coincidence. other then that concerta does not have a direct cause to contracting anything.
hope that helps
I just started taking Concerta (36 mg) and I immediately developed shingles. My doctor swears it's a coincidence, but after seeing your post I can't help but wonder. I had chicken pox as a child, but I've never had shingles before now. What happened in your case? I went to the doctor today and got neurontin and valtrex, but the doctor told me to keep taking the Concerta. I don't know what to do.
Put it into your search Engine under Herpes Zoster/Concerta and see if anything comes up.