Humid weather, physical activity, certain clothing fabrics, overheating, can all lead to
heat rash. There is inflammation, formation of blisters and itchy rash. Contact dermatitis is another possibility caused due to contact with any allergen. Jock itch, or tinea cruris, is a fungal infection caused by the fungus Trichophyton rubrum. It causes an itching annoying rash in the groin area, buttocks, and inner thighs .Application of Clotrimazole cream may provide relief. Maintain local hygiene.