Cannabigerol and standardized full-spectrum cannabis extract effects in acute and chronic inflammatory pain models.

Escobar-Espinal D.; Alves Fernandes T.; Ponciano R.; Borges L.; de Mattos B.; Hallak J.; Crippa J.; Guimarães F.; Del-Bel E.; Pedrazzi J. et al. · Psychopharmacology · 2026

**Background & Methods** This preclinical study evaluated cannabigerol (CBG) and standardized full-spectrum cannabis extract (FULL) in male Wistar Hannover rats using acute (formalin test) and chronic (complete Freund's adjuvant/CFA) inflammatory pain models. Treatments were administered at varying doses before the formalin test and after CFA initiation as either single or repeated daily doses over 21 days, with assessment of analgesia, motor function, and inflammatory markers (TNF-α, IL-10). **Key Findings** • **Acute pain response**: Both cannabinoids reduced nociceptive behaviors during the initial phase of formalin testing (Phase I); however, only FULL sustained analgesia through Phase II, suggesting differential pharmacodynamic profiles between the two formulations. • **Chronic pain management**: Single-dose administration showed minimal efficacy, while repeated high-dose treatment improved mechanical pain thresholds. FULL demonstrated earlier analgesic onset (day 10), whereas CBG achieved sustained baseline sensitivity restoration from day 15 onward, indicating slower but potentially more durable effects. • **Anti-inflammatory effects and region-specificity**: Both cannabinoids prevented CFA-induced TNF-α elevation in the spinal cord and plasma; however, elevated TNF-α in dorsal root ganglia (DRG) persisted despite treatment, revealing region-specific inflammatory regulation. IL-10 levels remained unaffected. Both compounds preserved motor function by preventing CFA-induced locomotor impairments (except CBG at lowest dose). **Dosage & Administration** CBG and FULL were administered at 10 mg/kg as the optimal dose, with comparative lower-dose groups evaluated. Route of administration not specified in abstract. **Safety & Adverse Effects** Not reported. Motor impairment assessments indicated preserved locomotor function, but specific adverse effect monitoring data were not detailed. **Evidence Quality** This is a preclinical animal study with significant limitations: findings in rodent pain models may not translate directly to human chronic inflammatory pain conditions. The lack of mechanistic detail regarding CBG versus FULL active constituents, absence of behavioral observation beyond analgesia and locomotion, and limited cytokine profiling (TNF-α, IL-10 only) restrict interpretation. The study provides moderate evidence for cannabinoid efficacy in experimental inflammatory pain but requires human clinical validation before clinical recommendations can be established.

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