CBD/THC Extract Did Not Improve Pain Outcomes After Knee Surgery in Dogs | Research

The takeaway

A randomized, double-blind trial in 42 dogs found that adding CBD:THC extract to standard post-surgical pain management did not improve pain, mobility, or recovery after knee surgery compared to placebo.

Pet owners considering CBD for dog pain and veterinarians advising on post-surgical pain management.

No significant differences in any outcome measure between CBD and placebo groups

What the researchers found

There were no significant differences in pain scores, range of motion, thigh circumference, or gait symmetry between dogs receiving CBD:THC extract and those receiving placebo, when both groups also received standard analgesics. Minor benefits from the higher dose appeared only on day 1 and did not persist. No serious adverse events occurred.

Why it matters

Pet owners increasingly give CBD products to dogs for pain, often based on anecdotal reports. This controlled trial found that when added to standard pain management, CBD did not provide additional benefit for post-surgical pain.

The numbers in context

48 dogs enrolled, 42 completed. Three groups: placebo, 2 mg CBD/kg, 5 mg CBD/kg (20:1 CBD:THC). Glasgow pain scores, range of motion, gait symmetry assessed. No significant group differences. Plasma cannabinoid levels were highly variable. Mild GI effects in 7 cases.

How the study worked

Randomized, double-blinded, placebo-controlled trial of 48 dogs (42 completers) undergoing TPLO knee surgery. Three groups: placebo, low CBD (2 mg/kg), and high CBD (5 mg/kg) with a 20:1 CBD:THC ratio. All dogs received standard analgesics. Assessments at days 1 and 14 post-surgery. Published in Frontiers in Veterinary Science.

What this study cannot tell us

Small sample size per group. Only one CBD:THC ratio tested. Standard analgesic protocol was comprehensive, possibly leaving little room for additional improvement. 14-day follow-up only. Variable plasma cannabinoid levels suggest inconsistent absorption.

How to read the evidence

Moderate: well-designed double-blind RCT but small sample, variable absorption, and only one formulation tested.

When this study was published

2025 study (2022-2024 enrollment).

The bigger picture

This adds to evidence that CBD may not provide additional pain relief beyond standard analgesics. The negative result is important because it helps prevent unnecessary supplementation and directs attention toward proven pain management strategies.

Questions still open

Would CBD help when standard analgesics are inadequate? Could different CBD:THC ratios show different results? Does the highly variable plasma absorption mean some dogs simply did not get enough CBD?

Common questions

Should I give my dog CBD after surgery?

This controlled study found no benefit from adding CBD to standard post-surgical pain management. Standard analgesics alone were effective regardless of CBD treatment.

Was CBD safe for the dogs?

No serious adverse events were reported. Seven cases had mild gastrointestinal effects (vomiting or diarrhea). Owners reported the CBD doses were generally well tolerated.

Read the original research

Efficacy of a 20:1 CBD:THC cannabis herbal extract for pain and inflammation in dogs following tibial plateau leveling osteotomy.

Frontiers in veterinary science, 12, 1676779

View on PubMed ↗Publisher’s paper ↗

Citation

Lyons, Chloe; Pinto, K Romany; Penney, Kira; Holmes, Laura; Salama, Abdul; Alcorn, Jane; Chicoine, Alan. (2025). Efficacy of a 20:1 CBD:THC cannabis herbal extract for pain and inflammation in dogs following tibial plateau leveling osteotomy.. Frontiers in veterinary science, 12, 1676779. https://doi.org/10.3389/fvets.2025.1676779