The present invention is drawn to adhesive formulations and methods of drug delivery. The formulation can include a drug, a solvent vehicle, and a solidifying agent. The solvent vehicle can include a volatile solvent system including at least two volatile solvents, and a non-volatile solvent system including at least one non-volatile solvent, wherein at least one non-volatile solvent is capable of facilitating the delivery of the drug at therapeutically effective rates over a sustained period of time. The formulation can have a viscosity suitable for application to a skin surface prior to evaporation of the volatile solvents system. When applied to the skin, the formulation can form a solidified layer after at least a portion of the volatile solvent system is evaporated.