Topical and oral preparations of nicotinamide (the amide form of vitamin B3) are alternative medical treatments. Nicotinamide reportedly improves acne due to its anti-inflammatory properties, its ability to suppress sebum production, and its wound healing properties. Topical and oral preparations of zinc are suggested treatments for acne; evidence to support their use for this purpose is limited. Zinc's capacities to reduce inflammation and sebum production as well as inhibit "C. acnes" growth are its proposed mechanisms for improving acne. Antihistamines may improve symptoms among those already taking isotretinoin due to their anti-inflammatory properties and their ability to suppress sebum production.