According to an experimental study with healthy cannabis users the combination of the opioid oxycodone and cannabis reduced pain assessed using the Cold-Pressure Test. Participants received either 2.5 or 5 mg of oxycodone or a placebo together with smoked cannabis with 5.6 % THC or no THC and immersed one hand in cold water. Researchers of the New York State Psychiatric Institute and Department of Psychiatry of the Columbia University, USA, measured the time to report pain (pain threshold) and to withdraw the hand from the water (pain tolerance).
Alone, 5.0 mg oxycodone increased pain threshold and tolerance. Although active cannabis and 2.5 mg oxycodone alone failed to elicit analgesia, combined they increased pain threshold and tolerance. authors concluded that “cannabis enhances the analgesic effects of sub-threshold oxycodone, suggesting synergy.”
Cooper ZD, Bedi G, Ramesh D, Balter R, Comer SD, Haney M. Impact of co-administration of oxycodone and smoked cannabis on analgesia and abuse liability. Neuropsychopharmacology. 2018 Feb 5. [in press]