CBD Reduces Both Pain and Anxiety in Rats — But Anxiety-Prone Animals Respond Differently | Research

The takeaway

Chronic CBD treatment reduced nerve pain across all rat lines but had differential anxiety effects — helping anxiety-prone rats less, suggesting individual anxiety traits may affect CBD treatment response.

Pain researchers, anxiety disorder specialists, personalized medicine advocates, CBD clinicians

What the researchers found

CBD (5 mg/kg daily for 10 days) reduced allodynia across all rat lineages bred for different anxiety levels, though anxiety-prone (CHF) rats showed less benefit. CBD was anxiolytic for control and high-anxiety rats with nerve injury but not for low-anxiety rats. CBD reduced conditioned fear in all non-injured groups but not in anxiety-prone rats with nerve injury. BDNF expression varied by lineage.

Why it matters

Anxiety and chronic pain commonly co-occur, and CBD is increasingly used for both. This study reveals that individual differences in anxiety-proneness affect CBD's therapeutic profile — important for personalizing treatment.

The numbers in context

5 mg/kg CBD daily, days 14-23 post-surgery. Three lineages tested. CBD reduced allodynia in all lineages (less in CHF). Anxiolytic in CTL and CHF with CCI. BDNF restored in CTL rats by CBD treatment.

How the study worked

Male rats from three selectively bred Carioca lineages (high-freezing CHF, low-freezing CLF, non-selected CTL; n=32/group) underwent sciatic nerve injury or sham surgery, then received CBD 5 mg/kg daily for 10 days. Sensory, locomotor, anxiety, and fear conditioning outcomes assessed.

What this study cannot tell us

Male rats only. Single CBD dose tested. Rat breeding lineages are models, not direct analogs of human anxiety disorders. 10-day treatment may not reflect chronic use. BDNF effects varied unpredictably across lineages.

How to read the evidence

Well-designed preclinical study with validated anxiety model, limited by single sex, single dose, and animal-to-human translation challenges.

When this study was published

Published 2026 using the validated Carioca rat anxiety model.

The bigger picture

The differential response across anxiety phenotypes suggests a future where CBD treatment for pain and anxiety is personalized based on individual psychological profiles — not a one-dose-fits-all approach.

Questions still open

Would higher CBD doses benefit anxiety-prone individuals more? Do human anxiety traits predict CBD treatment response? Could BDNF levels serve as a biomarker for CBD responsiveness?

Common questions

Does CBD help with both pain and anxiety?

In this rat study, CBD reduced nerve pain across all anxiety types but had variable anxiety effects — it helped control and high-anxiety rats more than low-anxiety ones, and anxiety-prone rats with nerve injury responded least.

Does your anxiety level affect how CBD works?

This study suggests yes — rats bred to be more anxiety-prone showed less pain relief from CBD and didn't benefit from its anti-anxiety effects when they also had chronic pain, suggesting individual anxiety traits influence CBD response.

Read the original research

Chronic cannabidiol treatment effects on contextual fear and neuropathic pain in Carioca rats high and low conditioned freezing.

Behavioural brain research, 496, 115855

View on PubMed ↗Publisher’s paper ↗

Citation

Macêdo-Souza, Carolina; Ferrarese-Tiballi, Aline A; Maisonnette, Silvia Soares; Rosseti, Flávia; Catalão, Carlos Henrique Rocha; Hallak, Jaime E; Crippa, José A; Zuardi, Antônio W; Landeira-Fernandez, J; Leite-Panissi, Christie Ramos Andrade. (2026). Chronic cannabidiol treatment effects on contextual fear and neuropathic pain in Carioca rats high and low conditioned freezing.. Behavioural brain research, 496, 115855. https://doi.org/10.1016/j.bbr.2025.115855