A fungal skin infection like Tinea Corporis (ringworm) is frequently the cause of itching around the neck, upper chest, and sides with spreading "ring-like" or patchy lesions. In warm, sweaty places, it normally spreads slowly and gets more irritating. Don't share towels or clothes, wear loose cotton clothing, keep the region dry and clean, and refrain from scratching. Steroid-mixed creams can exacerbate and spread fungal infections, so avoid using them. A doctor-recommended antifungal lotion, such as terbinafine or clotrimazole, is typically required for a few weeks. You should consult a dermatologist if the rash is getting worse, spreading every day, or is really itchy. For a complete recovery, you could require stronger medication or oral antifungal tablets.