Conan has hives! I noticed that he had a few "mosquito bites" after playing outside all day Friday. Then when I undressed him for his bath I realized it must be something more than just mosquito bites, because they were all over his arms and legs! There were red patches, about the size of a silver dollar but irregularly shaped, with several small raised bumps (like fresh mosquito bites) clustered within each patch. I gave him a bath and treated the bumps topically with a hydrocortisone anti-itch cream, but a couple hours after being put to bed he woke up covered in NEW itchy splotches, all in different places. More anti-itch cream got us through the night, but in the morning he was again covered in welts.
He seemed fine after more anti-itch cream and some breakfast cartoons, and it was a nice day, so we headed outside to play. Sure enough, after being outside for a couple of hours the itchy splotches were back, worse than ever. A little research on the internet and we had a diagnosis: Hives. I took a trip to the drugstore for a bottle of benedryl and gave him a dose when he woke up from his nap. It was amazing: all the spots disappeared 20 minutes after giving him the medicine. Whew.
According to the information at AskDrSears.com we'll probably never be able to determine exactly what Conan is having a reaction to. It seems pretty clear that it's something outside right now, which makes me think that it is a pollen because the first few trees and flowers of spring are beginning to bloom. Indeed, today he woke up without any itchy splotches, but after being outside again broke out in hives. At least now we have the benedryl at the ready!