Abstract: An oil in water microemulsion or sub-micron emulsion composition for dermal delivery of at least one pharmaceutically active ingredient, is provided. The composition includes an oil phase dispersed throughout a water phase, the oil phase including at least one member selected from the group consisting of an animal oil, a mineral oil, a vegetable oil, a silane member, a siloxane, an ester, a fatty acid, a fat, a halogen compound, and an alkoxylated alcohol; and at least one lipophilic surfactant, the water phase including at least one hydrophilic surfactant, water and optionally a non-surfactant amphiphilic compound, the weight ratio of the at least one hydrophilic surfactant to the at least one lipophilic surfactant being approximately 9.0:1.0 to 2.0:3.0.