I ask because we don't even know why you're taking it, what condition you have, and even if we did, no one here is likely to be able to give you a safe answer about how your particular situation and meds will interact with creatine. Sorry.
You should ask your doctor if he is OK with you taking creatine, even if he mistakenly believes it does nothing (which does not say that much positive about him as it's well established that creatine is effective).