Prolonged previous cannabis consumption and the substantial overlap between recreational and medicinal cannabis use highlight the challenges in obtaining a tenable definition of medicinal cannabis therapy.

Background: This study examined whether a perioperative regimen of pregabalin added to celecoxib improved pain scores and functional outcomes postdischarge up to 3 months after total hip arthroplasty (primary outcome) and acute postoperative pain and adverse effects (secondary outcomes). Methods: One hundred and eighty-four patients were enrolled in a randomized, double-blind, placebo-controlled study. Two hours before receiving a spinal anaesthetic and undergoing surgery, patients received celecoxib 400 mg p.o. and were randomly assigned to receive either pregabalin 150 mg p.o. or placebo p.o. After surgery, patients received pregabalin 75 mg or placebo twice daily in hospital and for 7 days after discharge. Patients also received celecoxib 200 mg every 12 h for 72 h and morphine i.v. patient-controlled analgesia for 24 h. Pain and function were assessed at baseline, 6 weeks, and 3 months after surgery. Results: There was no difference between groups in physical function or incidence and intensity of chronic pain 3 months after total hip arthroplasty. The pregabalin group used less morphine [mean (): 39.85 (28.1) mg] than the placebo group [54.01 (31.2) mg] in the first 24 h after surgery (P<0.01). Pain scores were significantly lower in the pregabalin group vs the placebo group on days 1-7 after hospital discharge, and the pregabalin group required less adjunctive opioid medication (Percocet) 1 week after hospital discharge (P<0.05). Conclusions: Perioperative administration of pregabalin did not improve pain or physical function at 6 weeks or 3 months after total hip arthroplasty. Perioperative administration of pregabalin decreased opioid consumption in hospital and reduced daily pain scores and adjunct opioid consumption for 1 week after discharge.