Mike:
I don't know what your other dermatologists suggested, bt the only treatment I know of for your kind of problem is to pretreat with an antihistamine. In other words, 30-60 minutes before shower or
exerciseAerobic exercise
Aging and exercise
Asthma
Benefit of regular exercise
Bone-building exercise
Diabetes and exercise
Exercise - a powerful tool
Exercise - dress appropriately
Exercise and age
Exercise and weight loss
Exercise can lower blood pressure, take an antihistamine--Benadryl 25 mg or chlortrimeton 4 mg are over-the-counter, but if these don't work or are too sedating, there are prescription antihistamines like
AllegraAllegra
Allegra -d 24 hour
Allegra-d or
ClaritinClaritin
Claritin reditab
Claritin-d
Claritin-d 24 hour. It's a nuisnace to take these pills, but if they work, it may be worth it. At any rate, I think it's worth a try.
Best.
Dr. Rockoff