sentences:  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.Hydroquinone lightens the skin when applied topically by inhibiting tyrosinase, the enzyme responsible for converting the amino acid tyrosine to the skin pigment melanin, and is used to treat acne-associated post-inflammatory hyperpigmentation.