Volume VII: Research Gaps and Future Equine Studies

Volume VII: Research Gaps and Future Equine Studies

Volume VII: Research Gaps and Future Equine Studies

Purpose

This volume explains exactly what still needs to be studied before cannabinoid products can become evidence-based equine treatments.

The absence of research does not prove that a treatment works or does not work. It means a question remains unanswered.

Research Gap 1: Topical THC for Equine Arthritis

No substantial body of controlled research has established whether topical THC:

  • Penetrates equine skin
  • Reaches joint tissue
  • Reduces synovitis
  • Changes lameness
  • Improves range of motion
  • Reduces pain scores
  • Produces systemic THC exposure
  • Creates intoxication or behavioral effects

Ideal future study

A randomized, blinded, placebo-controlled trial involving horses with naturally occurring osteoarthritis.

Researchers would compare:

  • Placebo balm
  • CBD-only balm
  • Low-THC balm
  • Standard veterinary treatment

Outcomes could include:

  • Objective gait analysis
  • Force-plate measurements
  • Joint circumference
  • Flexion response
  • Veterinarian pain scoring
  • Owner quality-of-life scoring
  • Blood cannabinoid concentrations
  • Skin reactions
  • Drug-test detection

Research Gap 2: Skin Penetration

Researchers need to determine how deeply cannabinoids move through equine skin.

Important variables include:

  • Hair clipping
  • Skin thickness
  • Application site
  • Carrier oil
  • Occlusive bandaging
  • Concentration
  • Frequency
  • Heat
  • Massage
  • Damaged versus intact skin

A balm that affects superficial skin receptors may not reach a deep joint.

Research Gap 3: CBD Versus THC

Most equine administration studies involve CBD.

Research is needed to compare:

  • CBD
  • THC
  • CBDA
  • THCA
  • CBD and THC combinations
  • Isolated compounds
  • Full-spectrum extracts

CBD results cannot automatically be used as evidence for THC because the compounds have different receptor activity, psychoactive potential, metabolism and safety concerns.

Research Gap 4: Equine Dose Finding

Researchers have not established a universal therapeutic cannabinoid dose for equine pain.

Future studies must identify:

  • Lowest effective dose
  • Highest tolerated dose
  • Dosing interval
  • Accumulation
  • Withdrawal period
  • Effect of body condition
  • Effect of age
  • Effect of feeding
  • Effect of disease

Research Gap 5: Long-Term Safety

Longer trials are needed to assess:

  • Liver function
  • Kidney function
  • Gastrointestinal health
  • Neurological effects
  • Behavior
  • Appetite
  • Endocrine function
  • Insulin response
  • Reproductive safety
  • Immune effects
  • Medication interactions

A short-term study cannot answer every long-term safety question.

Research Gap 6: Senior and Arthritic Horses

Senior horses are a logical research population because they frequently experience:

  • Osteoarthritis
  • Reduced mobility
  • Muscle loss
  • Chronic inflammation
  • Multiple medications
  • Metabolic disease

However, those same factors may also increase the risk of side effects and drug interactions.

Research Gap 7: Laminitis

The 2025 hoof-receptor study provides a biological foundation, but researchers still need to determine whether manipulating the endocannabinoid system affects:

  • Acute laminitis pain
  • Lamellar inflammation
  • Insulin-associated laminitis
  • Supporting-limb laminitis
  • Lamellar-cell survival
  • Coffin-bone rotation or sinking
  • Recovery and recurrence

Cannabinoid experimentation should never delay emergency laminitis treatment.

Research Gap 8: Wounds and Skin Disease

The controlled equine wound study did not demonstrate improved healing from topical CBD.

Future research should examine:

  • Different CBD concentrations
  • THC-free versus THC-containing formulas
  • Different carriers
  • Chronic versus fresh wounds
  • Proud flesh
  • Sarcoids
  • Sweet itch
  • Dermatitis
  • Rain rot
  • Local pain and itching
  • Infection risk
  • Scarring

Each condition requires separate evidence.

Research Gap 9: Product Standardization

Clinical research requires products with verified:

  • Cannabinoid concentration
  • THC content
  • Terpene profile
  • Carrier ingredients
  • Stability
  • Shelf life
  • Microbial purity
  • Pesticide testing
  • Solvent testing
  • Heavy-metal testing

Without product standardization, two products labeled “equine CBD balm” may deliver very different exposures.

Research Gap 10: Objective Pain Measurement

Pain can be difficult to measure in horses.

Future cannabinoid studies should combine:

  • Equine pain scales
  • Facial-expression scoring
  • Objective gait analysis
  • Pressure or thermal thresholds
  • Activity monitors
  • Joint examination
  • Caregiver observations
  • Quality-of-life assessment

Owner reports are valuable, but they should not be the only outcome.

Research Gap 11: Topical Safety and Accidental Ingestion

Future studies should examine:

  • Skin irritation
  • Photosensitivity
  • Allergic response
  • Effects on damaged skin
  • Oral exposure from licking
  • Transfer between horses
  • Handler exposure
  • Use beneath wraps or boots
  • Repeated whole-limb application

Topical does not automatically mean risk-free.

Research Gap 12: Competition Withdrawal Guidance

Additional controlled research is needed to establish:

  • Detection times after oral use
  • Detection after topical use
  • Differences between CBD and THC
  • Effects of repeated application
  • Environmental hemp exposure
  • Reliable laboratory markers
  • Evidence-based withdrawal recommendations

Until those data exist, competition use remains especially uncertain.