Thanks guys. Have tried the calamine lotion but it's everywhere so I pretty much have to bathe in it I think. Telfast has helped a bit so far and I haven't needed in the last couple of days. The weirdest part is that it's only me... noone else has heat rash or anything - must be just another joy of being pregnant over summer - I didn't have that to deal with with DS so it's a whole different journey!