Table 4 Measured effect on pain and opioid use of cannabinoids in identified studies

Beaulieu [17]

Verbal scale (0–10) placebo, ketoprofen, 1 mg, 2 mg nabilone:

Pain at rest: 3.8 ± 0.6, 3.4 ± 0.3, 4.4 ± 0.3, 5.9 ± 0.6*, p = 0.0073

Pain with movement: 5.9 ± 0.5, 5.6 ± 0.3, 6.3 ± 0.5, 7.7 ± 0.5*, p = 0.0187

*significantly different

mg morphine via PCA

placebo, ketoprofen, 1 mg, 2 mg nabilone:

43.3 ± 8.2, 36.9 ± 5.9, 39.0 ± 6.8, 45.4 ± 8.1, p = 0.84

Haroutounian et al. [26]

Baseline vs. 6 months:

S-TOPS: 83.3 (95% CI 79.2-87.5) to 75.0±4.2 (95% CI 70.8-79.2), p < 0.001

BPI Baseline vs. 6 months:

Severity 7.5 (95% CI 6.75-7.75) to 6.25 (95% CI 5.75-6.75), p < 0.001

Interference: 8.14 (95% CI 7.28-8.43) to 6.71 (95% CI 6.14 to 7.14) p < 0.001

Number of subjects on opioid therapy at baseline and at 6 months:

73 to 41, p < 0.001

MME/day:

60 (95% CI 45–90) to 45 (95% CI 30–90) p = 0.19

Hickernell et al. [9]

Pain via VAS dronabinol vs. control:

POD 0: 3.2 ± 2.9, 3.0 ± 3.1, p = 0.7

POD 1: 3.0 ± 2.2, 3.3 ± 2.7 p = 0.48

POD 2: 3.3 ± 2.8, 3.4 ± 2.8 p = 0.85

POD 3: 3.0 ± 2.6, 2.5 ± 2.8 p = 0.53

Dronabinol vs. control:

Total MME during stay:

252.5 ± 131.5, 313.3 ± 185.4, p = 0.088

MME/length of stay:

121.7 ± 76.3, 131.5 ± 111.7, p = 0.48

Holdcroft et al [25]

Sum of VRS scores (0–4) from 0.5 to 6 h post-operatively

Sum of pain intensity differences at 5, 10, 15 mg:

at rest 3,3,5, p = 0.01

with movement 0, 1, 1, p = 0.7

Total pain relief at 5, 10, 15 mg: 4, 11, 14, p = 0.17

Rescue analgesia used in % of subjects in 5, 10, and 15mg groups: 100%, 50%, 25%, p < 0.0001

NNT to prevent 1 use of rescue analgesia (relative to 5 mg group)

2.0 (95% CI, 1.5–3.1 with 10 mg,

1.3 (95% CI 1.1–1.7) with 15 mg

Hunter et al.^a [18]

Reduction in worst pain (VAS) after 12 weeks of placebo, 250, or 500 mg/day: − 2.37, − 2.64, and − 2.83, no p value given. Not statistically significant.

Reduction in worst pain after 12 weeks of placebo in men receiving 250 mg/day vs. placebo: − 2.68, − 1.70, p = 0.049

Not assessed

Jain et al. [19]

Pain intensity 15 min to 6 h on 4-point scale (0–3), Pain relief on 5 point scale (0–4), Pain analog (0–25)

Area under difference curve of pain intensity, relief, and analog:

Placebo: 5.20, 9.87 36.32, 1.94

1.5 mg: 9.95*, 16.48*, 71.58**, 3.33*

2.0 mg: 9.84*, 16.90**, 70.33**, 3.30*

2.5 mg:11.26**, 19.10**, 77.61**, 3.50**

3.0 mg 9.10*, 16.08*, 61.18*, 3.90*

*p < 0.05, **p < 0.01 (placebo vs. levonantradol).

Not assessed

Levin et al.20

0–10 NRS nabilone vs. placebo, score (SD):

NRS 30 min postop (rest) 2.68(3.22), 3.15 (3.41), p = 0.47

NRS 30 min postop (movement) 2.75 (3.17), 3.29 (3.42), p = 0.70

Maximum pain score (rest) 3.17 (3.15), 3.68 (3.25) p = 0.43

Maximum pain score (movement) 3.34 (3.30), 4.0 (3.33) p = 0.92

10 mg morphine equivalent (SD)

nabilone vs. placebo

Intraoperative:

21.3 (15.2) 20.0 (13.4) p = 0.40

Post-operative:

5.79 (9.2) 5.35 (6.9) p = .62

Mondello et al. [27]

NRS (0–10) baseline vs. 12 months treatment with THC/CBD

8.15 ± 0.98, 4.72 ± 0.9, p < 0.0001

BPI baseline vs. 12 months of THC/CBD:

General activities 6.72 ± 0.90, 3.63 ± 0.67, p < 0.001

Mood 5.54 ± 0.52, 3.63 ± 0.50, p < 0.001

Walking abilities 6.45 ± 0.82, 3.27 ± 0.78, p < 0.001

Normal work 5.90 ± 0.94, 3.27 ± 0.46, p < 0.001

Relations with other people 6.09 ± 1.04, 3.09 ± 0.94, p < 0.001

Sleep 6.09 ± 1.44, 3.90 ± 1.30, p < 0.01

Enjoyment of life 6.18 ± 0.87, 3.54 ± 1.03, p < 0.001

Not assessed

Notcutt et al. [22]

Primary pain location VAS:

(median (interquartile range))

placebo 5.9 (2.8–7.3)

THC 4.63 (1.74–6.06*, p < 0.05

THC:CBD 4.4 (2.6–5.8)*, p < 0.01

CBD 5.45 (3.6–7.4)

*Significantly different from placebo

Not assessed

Poli et al. [28]

VAS median score at baseline, 1, 3, 6, and 12 months:

9,7,6,5,5 Friedman test, χ² = 61.375 , p < 0.001

Not assessed

Ware et al. [21]

VAS average pain intensity

6.78 to 5.54 after 12 months of MCT

5.89 to 6.10 after 12 months in control group

McGill Pain Questionnaire total score:

32.29 to 27.50 after 12 months of MCT

26.55 to 26.88 after 12 months in control group

Not assessed

Yassin et al. [23]

VAS baseline vs. 12 months of MCT:

Intensity: 9.3 ± 1.3 to 3.3 ± 1.7, p < 0.01

Frequency: 8.7 ± 1.4 to 2.0 ± 2.0, p < 0.01

BPI at baseline, initiation, 6 months, and 12 months of MCT:

Severity: 9.2 ± 1.0, 8.6 ± 1.5, 2.7 ± 1.5, 1.1 ± 0.8, p < 0.01 ANOVA

Interference: 8.7 ± 1.4, 9.7 ± 1.1, 3.7 ± 1.5, 1.1 ± 0.8, p < 0.01 ANOVA

Morphine dose equivalents:

50.7 ± 33.7 prior to MCT

11.1 ± 21.5 after 12 months of MCT

p < 0.001

n = 27 stopped opioid therapy

Yassin et al. [24]

VAS baseline, initiation, 3 months, and 6 months of MCT:

8.1 ± 1.2; 8.1 ± 1.4; 5.3 ± 1.3; 3.3 ± 2.2, p < .0001 ANOVA

Opioid consumption significantly decreased