Given the time of year you posted your question, my guess would be that your inner thigh rash is most likely heat rash.
If you've tried ointments and creams with no success, maybe you should try powder with corn starch or something like Gold Bond powder (I'm pretty sure that's the right name) and see if this helps.
Also try to keep the area dry and sweat free. If you wear shorts, find some that won't bunch or chafe the area and that are long enough that your bare thighs don't rub together when you walk.
More input from FAQ Farmers:
Balmex works wonderfully to relieve the redness and irritation.
Answer
"Dermaid soft 1% cream" it is amazing. Use 3 times a day.
Answer:
I will suggest you to use Eurex lotion, one of the best solution for almost all sort ot itching. Eurax Lotion provides relief of itching and skin irritation caused by: sunburn, dry eczema, itchy dermatitis, allergic rashes, hives, nettle rash, chicken pox, insect bites and stings, heat rashes and personal itching. Treatment of scabies.
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