The invention relates to a medical device for delivering a therapeutic agent to a tissue. The medical device has a layer overlying the exterior surface of the medical device. The layer contains a therapeutic agent such as paclitaxel or rapamycine and an additive. The additive has a hydrophilic part and a hydrophobic part and the therapeutic agent is not enclosed in micelles or encapsulated in particles or controlled release carriers. In a preferred embodiment, the additive comprises ascorbyl palmitate, polyglycerol-10 oleate, octoxynol-9, ?-isononylphenoxypolyglycidol, tyloxapol, niacinamide, thiamine hydrochloride, nicotinic acid, 2-pyrrolidone-5-carboxylic acid or albumin.