Pharmaceutical and nutraceutical compositions suitable for transdermal administration of plant-derived medicinal compounds are disclosed. The compositions comprise ground plant material (plant flour) and a dermally acceptable adhesive. In preferred embodiments, the plant flour is derived from Cannabis sp. and the adhesive is a polymer selected from the group consisting of acrylic polymers, silicone polymers, urethanes, isobutylenes, polyisobutylenes, vinyl acetate, and styrene polymers or copolymers.