Red dots on legs. benadryl (diphenhydramine) didn't work. had it once before, went away and came back now its spread to my legs, and is bigger?

See a doctor or call: In and show a picture to the HealthTap doctors. The dermatologists I know always say if there is a rash, you have to see it to make a diagnosis. Since rashes are very common and non specific, you need a doctor to look at it, possibly feel it, examine the rest of you and take a history. Then, after you have a diagnosis, a treatment plan can be made. Best wishes!