Testing 32 Cannabinoids Revealed Some Were More Effective Than THC at Lowering Eye Pressure

A systematic screening of 32 cannabinoids in rabbits found that certain THC derivatives were more effective than THC itself at reducing eye pressure, and non-THC cannabinoid compounds also showed activity.

ElSohly, M A et al.·Current eye research·1984·Preliminary EvidenceAnimal StudyAnimal Study
RTHC-00027Animal StudyPreliminary Evidence1984RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Animal Study
Evidence
Preliminary Evidence
Sample
Not reported

What This Study Found

Researchers systematically tested 32 different cannabinoid compounds for their ability to reduce intraocular pressure (IOP) in rabbits. The tested compounds included derivatives and metabolites of both delta-9-THC and delta-8-THC, other natural cannabinoids, synthetic cannabinoids, and even some non-cannabinoid compounds found in the cannabis plant.

Most compounds were tested intravenously, with a few also tested topically in mineral oil. Water-soluble derivatives of delta-9-THC and delta-8-THC were synthesized specifically for topical testing in aqueous solution.

The key findings: certain THC derivatives were more active at lowering eye pressure than the parent THC compounds. Additionally, compounds other than THC and its derivatives also demonstrated IOP-lowering activity, broadening the range of potential therapeutic candidates for glaucoma.

Key Numbers

32 different cannabinoids tested. Included delta-9-THC and delta-8-THC derivatives, metabolites, natural cannabinoids, and synthetic compounds. Some derivatives were more active than parent compounds.

How They Did This

Screening study in rabbits testing 32 cannabinoid compounds for intraocular pressure reduction. Most compounds were administered intravenously; selected compounds were tested topically in mineral oil or as water-soluble aqueous solutions.

Why This Research Matters

This study expanded the therapeutic search beyond THC itself. By identifying non-THC cannabinoids with IOP-lowering activity, it opened the door to developing glaucoma treatments that might avoid the psychoactive side effects of THC.

The Bigger Picture

While cannabis-based glaucoma treatments never became mainstream (IOP-lowering drugs like prostaglandin analogs proved more practical), this study was important for establishing that the cannabis plant contains multiple compounds with potential therapeutic activity beyond THC alone, a concept central to modern cannabinoid medicine.

What This Study Doesn't Tell Us

Animal study in rabbits; IOP responses may differ in humans. Most compounds were tested intravenously, which does not reflect a practical route of administration for glaucoma patients. Topical testing was limited to a few compounds.

Questions This Raises

  • ?Which specific cannabinoid derivatives showed superior IOP-lowering activity?
  • ?Can these be formulated for practical topical delivery in humans?
  • ?Do the non-THC active compounds also produce psychoactive effects?

Trust & Context

Key Stat:
32 cannabinoid compounds tested for eye pressure reduction
Evidence Grade:
An animal screening study providing pharmacological data across many compounds. Valuable for identifying candidates but not directly applicable to human treatment.
Study Age:
Published in 1984. Modern glaucoma treatment relies on prostaglandin analogs and other drug classes rather than cannabinoids.
Original Title:
Cannabinoids in glaucoma II: the effect of different cannabinoids on intraocular pressure of the rabbit.
Published In:
Current eye research, 3(6), 841-50 (1984)
Database ID:
RTHC-00027

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal StudyOne case or non-human subjects
This study

Tests effects in animals (usually mice or rats), not humans.

What do these levels mean? →

Frequently Asked Questions

Were any compounds better than THC?

Yes. Certain derivatives of both delta-9-THC and delta-8-THC were more active at lowering eye pressure than the parent THC compounds.

Did only THC-related compounds work?

No. The study also found that compounds other than THC and its derivatives had IOP-lowering activity, including some non-cannabinoid compounds found in cannabis.

Read More on RethinkTHC

Cite This Study

RTHC-00027·https://rethinkthc.com/research/RTHC-00027

APA

ElSohly, M A; Harland, E C; Benigni, D A; Waller, C W. (1984). Cannabinoids in glaucoma II: the effect of different cannabinoids on intraocular pressure of the rabbit.. Current eye research, 3(6), 841-50.

MLA

ElSohly, M A, et al. "Cannabinoids in glaucoma II: the effect of different cannabinoids on intraocular pressure of the rabbit.." Current eye research, 1984.

RethinkTHC

RethinkTHC Research Database. "Cannabinoids in glaucoma II: the effect of different cannabi..." RTHC-00027. Retrieved from https://rethinkthc.com/research/elsohly-1984-cannabinoids-in-glaucoma-ii

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.