Disclosed are compositions and methods useful for enhancing the skin penetration of drug nanoparticles. The compositions can be hydrophobic and include a hydrophobic carrier, a volatile silicone fluid, and drug nanoparticles. Also disclosed are methods for inhibiting crystal growth of drug nanoparticles in an aqueous carrier or a hydrophobic carrier. Further, methods to topically treat psoriasis using compositions containing nanoparticles of paclitaxel or other taxanes are disclosed.
