Table 2.

Detailed description of excluded studies after full text review.

Articles	Study Design	Description	Age (Years)	Size	Outcome Pain Measures	Outcome Intervals	Reason for Exclusion
Hagenbach et al. (2007)	Prospective	Assess the efficacy and side effects of oral D9-THC and rectal THC-HS in SCI patients, but the rectal arm was not performed	29–66	21	Self-reported: spasticity sum score using the MAS, self-ratings of VAS and spasticity	Baseline, 8 and 43 days	Did not assess routes other than oral or inhalation
Phan et al. (2009)	Prospective	Explores the analgesic efficacy of adjuvant therapy with a topical cannabinoid agonist in PHN patients with facial involvement	48–79	8	VAS	Baseline, 2 and 4 weeks	Did not include a control group
Eskander et al. (2020)	Retrospective	Describes the use of a hemp-derived CBD in a topical cream for the symptomatic relief in acute and chronic back pain	40–61	2	VAS	Baseline, 8 h and 4 weeks	Case report without a control group
Jain et al. (1981)	Prospective	Evaluation of intramuscular levonantradol and placebo in acute postoperative pain in patients with moderate to severe postoperative or trauma pain	25.3 ± 5 30.2 ± 11	56	Four point scale	Baseline, 15, 30, and 60 min, and hourly thereafter for a total of 6 h	Did not include patients with neuropathic pain
Schindler et al. (2019)	Prospective	Psychoactive doses of intravenous D9-THC in healthy volunteers induce chemical pain and hyperalgesia with capsaicin, mechanical (von Frey filament), hot and cold (thermode), and electrical (pulse generator)	19–51	6	VAS, MPQ-SF	Before drug administration, peak drug effects, and 2 h after drug administration	Study performed in healthy subjects, did not include patients with neuropathic pain

THC, tetrahydrocannabinol; THC-HS, THC-hemisuccinate; SCI, spinal cord injury; MAS, Modified Ashworth Scale; VAS, visual analogue scale; PHN, postherpetic neuralgia; CBD, cannabidiol.