Calamine is a mixture of zinc carbonate (ZnCO3) with about 0.5% ferric oxide (Fe2O3). It is the main ingredient in calamine lotion and is used as an antipruritic (anti-itching agent, attributed to the presence of phenol in the formulation) to treat mild pruritic conditions such as sunburn, eczema, rashes, poison ivy, poison oak, 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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