101 patients undergoing an arthroscopic rotator cuff repair were randomized to receive 14 days of buccally absorbed cannabidiol (CBD; n=54; 25mg dose to those ≤80kg, 50mg dose to those >80 kgs) or placebo (n=47) for the control of postoperative pain. The primary outcome of interest was pain intensity measured with a Visual Analog Scale (VAS). Secondary outcomes of interest included patient satisfaction, opioid consumption, nausea, liver enzyme levels, and adverse events. Outcomes were assessed up to 14 days post-operation. Results revealed significantly less pain in the CBD group vs. placebo on Day 1 post-operation only. However, in the subgroup analysis by dose, the superiority in pain scores was only observed in the 50mg group vs. placebo. Patient satisfaction on day 1 and 2 post-operation were also significantly in favour of the CBD group; in the subgroup analysis by dose, this superiority was observed in the 50mg group vs. both the 25mg and placebo groups on day 1, and vs. the placebo group only on day 2. Severity of nausea was significantly greater in the 50mg group vs. the 25mg group.