A transdermal delivery composition for the delivery to
skin and the penetration of the
skin includes: (a) a therapeutic effective amount of a
cannabinoid mixture, wherein the
cannabinoid mixture comprises
cannabidiol (CBD) and Δ9-
tetrahydrocannabinol (THC) at a weight ratio of about 1:20 to about 20:1; (b) a hydrophilic
polymer /
hydrophobic polymer adduct in an amount sufficient to hold the
cannabinoid composition and provide a sustain release of the cannabinoid mixture after application to
skin tissue over a time period of at least 6 hours; (c) a penetrant component in an amount sufficient to assist with a
transdermal penetration of the cannabinoid mixture through
skin tissue once the composition has been applied to
skin tissue; (d) a surfactant component in an amount sufficient to stabilize the
polymer adduct and release the cannabinoid mixture from the transdermal delivery composition upon application to
skin tissue; and (e) at least about 70 wt. % water. A method of application of a transdermal delivery composition to skin tissue includes applying the transdermal delivery composition to skin tissue and spreading the composition to form a film on the skin tissue. A method for formulating a transdermal delivery composition based on a desired penetration weight ratio of CBD to THC through skin tissue includes selecting a formulation weight ratio of CBD to THC for formulating the composition, wherein the weight ratio is determined by multiplying the desired penetration weight ratio of CBD to THC by a CBD / THC delivery factor, wherein the CBD / THC delivery factor.