Hi, my skin has become dry in certain area. before getting dry it swells up and itches, with rash then it subsides and the skin becomes so dry (no longer stretches comfortably. i also have small pimples that come out pus. what could this be?

Sounds treatable: The location of that "certain area" or areas is key. If we are talking about places where skin contacts skin like the axilla or groin, then this is likely a simple fungal infection and will clear up with topical clotrimazole 1% cream available over the counter for athletes foot and other fungal infections. If more widespread there are effective oral meds. If painful hot red, or with fever see doc

Uncertain: These lesions would likely need to be examined and more history obtained to be able to provide you with useful input about the diagnosis or possible treatment.