Allergies frequently develop as we age... generally there are 3 "types" of allergies: those that get increasingly worse every time we're exposed, and those that are just "worse" to begin with ;) and those that fade over time.
As an ex) I'm deathly allergic to watermelon. No reaction to it at all (visible or "feel-able" until I was 11. Then the hives started. The the hives got as big as my palm. Then the hives started coating my mucous membranes (mouth/ throat/ etc.... UGH imagine feeling like you had swallowed 1000 mosquitos).By the end of the summer (and some empiracle testing) we knew what the culprit was. (That's the danger of having doctors in the family, btw... they have you sit and EAT the suspects, instead of getting scratch tests, since they're armed with "antidote") After not having watermelon for nearly 20 years I had the BEST gaspacho last summer. And my throat swelled shut. I had no idea the allergy had gotten that severe... I could still cut up watermellon for the kids... no reaction. Anyhow... I snorted some benedryl on the quick... which got my tongue and throat down to manageable proportions right quick... and managed to swallow some more benedryl. NOW I can't even touch watermellon. My son picked up a baby one at the store, put it down, touched my hand, and he left a red Kiddo sized hand print on my arm. Crazy. ((Especially since there's practically nothing TO watermelon. Sheesh.))
BUT the other 2 things to consider are:
- Yeast infection
- Does he lick his lips? And is the rash in the creases of his wrists. It MAY actually be nothing more than chapped skin (vaseline will help, but lotion of chapped / bleeding skin usually doesn't... unless it's Norweigan fisheman type lotion.