(±)-CP 55,940 is a bicyclic mimetic of Δ9-THC that binds both cannabinoid receptors and has potent analgesic properties. The isomer (-)-CP 55,940, which structurally resembles the A and C ring of Δ9-THC, is a potent analgesic. (+)-CP 55,940 is an enantiomer purified from the (±)-CP 55,940 racemic mixture. The functional characteristics of this isomer have not been studied. However, there is no significant difference between the racemate and (-) isomer in analgesic activity in four of five tests, suggesting that (+)-CP 55,940 is biologically active.