Neem kills the bacteria that cause acne and reduce the inflammation that makes it so noticeable. Neem-based creams have even improved the appearance of people who have reddened skin from acne that ended years before. To prevent and heal acne, first wash with neem soap, the use a neem face pack to soothe and tighten the skin. Finally, apply a neem-based lotion or cream to moisturize and condition the skin.