rash caused by the sun

I have just recently have been getting a rash on my arm and back
that look like small blisters they are single and in clusters. I
get them when I go outside in the sun. I'm using sun screen with a 30 spf. I have never had a problem with the sun until I had my daughter .Do you have any suggestions on what this is or how I can make my body less sun sensitive. I can't stay out of it because I have two active children.

[Alan Rockoff, MD]

Hard to tell without seeing them.  Are the arm and back areas exposed to the sun?  If so, try using a broad-specturm UVA/UVB sunscreen.  If that fails, try an antihistamine (chlortrimeton--over the counter-- one hour before exposure.  If those fail, you may have to cover up when you go outside, not necessarily such a bad idea anyway.

Best.

Dr. Rockoff

[pedro42]

I am having a simaler problem like that. when i get hot outside and even inside i get an itching sensation all over my body and a rash that looks like heat rash appears and sometimes itches so bad that i cant even move or it will be worse. I think it might be an allergic reaction to something outside but i'm not sure. i tried using benedryl and claritin(which the doctor prescribed)but i developed an immunity to claritin and i have no positive results from benedryl caplets. I can't even work out because of this. please help me out, i have no idea what is affecting me!