A pharmaceutical aerosol foam composition, comprising: an effective amount of a pharmaceutically active ingredient, wherein said pharmaceutically active ingredient is a vitamin or analogue thereof; an occlusive agent; an aqueous solvent; an organic cosolvent; wherein the pharmaceutically active ingredient is insoluble in both water and the occlusive agent; and the occlusive agent being present in an amount sufficient to form an occlusive layer on the skin, in use. hi a second embodiment, an oil-in water emulsion having a vitamin, an occlusive agent; an aqueous solvent; and an organic cosolvent, wherein the occlusive agent is present in an amount sufficient to form an occlusive layer on the skin.