Table 2.

Effects of Cannabinoid Receptor Agonists on Acute Postoperative Pain

References	Pain Origin and Treatment	Results and Remarks
Raft et al., 1977 [129]	Premedication for dental extraction n=10 - THC 0.022 mg/kg i.v. - THC 0.044 mg/kg i.v. - diazepam 0.157 mg/kg i.v. - placebo	Pain thresholds and psychiatric interviews were assessed, supplemented by tests of personality, depression and anxiety. THC analgesic effects less than that after diazepam and placebo, while pain detection thresholds were altered unpredictably with high THC doses. Three subjects at low-dose THC had a better analgesic effect than placebo but not diazepam. Six subjects preferred placebo to low-dose THC as an analgesic.
Jain et al., 1981 [70]	Postoperative or trauma pain n=56 Levonantradol 1.5, 2.0, 2.5, or 3.0 mg or placebo Single dose, i.m.	Double-blind. Significant analgesic effects of each dose of levonantradol (a synthetic cannabinoid) as compared to placebo. No dose-response differences. Side effects in 57% levonantradol, especially drowsiness and, less frequently, dry mouth, dizziness, “weird dreams,” mild hallucinations, nervousness, apprehension and confusion.
Buggy et al., 2003 [14]	Postoperative pain n=40 Elective abdominal hysterectomy THC 5 mg p.o. single dose 48 h after surgery	Randomised double-blind, placebo-controlled. No analgesic effect of THC in this paradigm. Randomisation took place when postoperative patient-controlled analgesia was discontinued on the second postoperative day.