What is the cause of irritated dry skin on the inner thighs by the groin area and how do I treat it?

Intertrigo. Intertrigo (rash of body folds) may be due to different causes, including irritant dermatitis, contact dermatitis, fungal disorder (tinea cruris), or a dermatosis such as flexural psoriasis. Proper evaluation by a primary care physician or dermatologist is necessary to properly diagnose and treat this condition.