Topical astringents are agents that cause skin cells or mucus membranes to contract or shrink, by precipitating proteins from their surface. When applied topically they dry, harden and protect the skin. They reduce bleeding from minor abrasions and are used to relieve skin irritations resulting from minor cuts, allergies, eczema, stretch marks, insect bites and so on. Topical astringents can be used in throat lozenges, mouthwash, creams, lotions, etc.