Calamine

Calamine is a mixture of zinc oxide (ZnO) with about 0.5% ferric oxide (Fe2O3). It is the main ingredient in calamine lotion and is used as an antipruritic (anti-itching agent) to treat mild pruritic conditions such as sunburn, eczema, rashes, poison ivy, chickenpox, and insect bites and stings. It is also used as a mild antiseptic to prevent infections that can be caused by scratching the affected area, and an astringent to dry weeping or oozing blisters and acne abscesses.

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