Good morning, My 82 y/o father has had intermittant arm pain (tender to touch, throbbing) in each arm. Full cardiology work-up (replacement aortic valve), and it seems to coincide with exposure to peroxide. Dentist told him to rince with it, arm pain for quite awhile, stopped peroxide pain went away. He accidently used a peroxide based toothpaste and pain came back. Stopped using and pain again went away. Can t seem to find much on peroxide allergy, have you heard of such a thing. Thanks, Mike Beck