medical testimonies database contains 9 testimonies from cannabis users with glaucoma
the complete collection of testimonies from medical users of cannabis, see our
medical testimony database.
you find that cannabis helps you with this, or any other, medical condition?
If so, please tell us about how it benefits you via this
form. Anonymous submissions welcome!
effect of cannabis on intraocular pressure (IOP) in normal subjects has been well
studied, however, the effect on glaucoma patients is less well known, with only
a handful of patients studied. Only one study used herbal cannabis, the rest have
Hepler & Frank study (1971) found that oral or smoked cannabis reduced intraocular
pressures in normal subjects for about 4 to 5 hours with "no indications
of any deleterious effects ... on visual function or ocular structure". They
concluded that cannabis may be more useful than conventional medications and probably
works by a different mechanism.
all of the studies using cannabinoids have been double-blind and placebo controlled.
Two studies were of the effects of oral or smoked THC on IOP in normal subjects.
Hepler et al. (1976) reported that the drop in IOP was dose-related. Jones et
al. (1981) found that tolerance to the effects quickly built up, and there was
a rebound in IOP to above baseline levels when treatment was stopped. Another
two studies used intravenous infusions of various cannabinoids. Perez-Reyes et
al. (1976) found that only the cannabinoids that had psychoactive effects produced
a drop in IOP. Cooler & Gregg (1977) reported a drop in IOP but increased
anxiety. The effects of cannabinoids on IOP were confirmed in numerous animal
experiments, reviewed by Adler & Geller (1986).
orally-taken synthetic cannabinoids have been investigated by Newell et al (1979)
and Tiedeman et al (1981). These were given to patients who already had a high
IOP. The cannabinoid BW146Y and Nabilone had the same efficiacy as smoked cannabis
(but still had a short duration). BW29Y however did not have any significantly
few studies on glaucoma patients all involve small numbers of patients. Hepler
et al. (1976) found that when THC was smoked for months at a time by glaucoma
patients, the effect on intraocular pressure stayed constant and there was no
deterioration of vision. However only 7 of the 11 patients showed the effect.
Merrit et al. (1980) carried out a double-blind and placebo controlled study on
18 patients and found a significant reduction in IOP but unwanted cardio-vascular
and pyschoactive side-effects.
cannabinoids directly to the eyes should remove the side-effects but is proving
difficult since they are not water-soluble. Merrit et al (1981) applied THC to
only one eye in 8 patients, but found an effect on IOP in both eyes suggesting
that the THC had been adsorbed into the bloodstream, rather than acting topically.
However his patients reported no pyschoactive side-effects. Two other studies
applying THC directly to the eye (as an eye drop) by Green et al (1982) and Jay
et al (1983) showed no reduction in IOP.
one report (Green et al, 1978) the solubility issues were to some extent overcome
by dissolving THC in mineral oil, and using the resultant mixture as an eyedrop.
THC, cannabinol, 8-alpha- and 8-beta-11-dihydroxy-delta-9-THC all produce a lowering
of IOP when topically adminstered to rabbits. They result in no psychoactive effects
and appear to be as efficacious as the traditional eye-drops used to reduce IOP
(e.g. Pilocarpine) and often work for longer periods of time.
non-psychoactive extract of cannabis was tested in combination with Timolol eye-drops
in patients with high IOP by West et al (1980). They found that the effects of
the two medications were complementary and were even effective in some cases where
other medications had failed.
mentioned above, there are other approaches to aiding glaucoma sufferers, including
attempting to provude some neural protection. More research on this approach (with
or without cannabis) needs to be done, but Yoles et al (1996) used a synthetic
cannabinoid HU-211 which is thought to have potential neuroprotective effects.
More recent (animal-based) studies by Beilin et al and Naveh et al have shown
that this particular cannabinoid also lowers IOP.
the research already done, much more seems to be needed in order to determine
the optimum way to help sufferers of glaucoma with cannabis-based medications,
if indeed they prove to be beneficial to sufferers compared to existing medications.
Amongst others, both the Australian National Task Force on Cannabis (Hall et al,
1994) and a National Institute of Health workshop have called for more research
to be done on this topic.
M.W., & Geller, E.B., (1986) Ocular effects of cannabinoids. In Cannabinoids
as Therapeutic Agents ed. R Mechoulam CRC Press pp51-70.
et al. (2000) Pharmacology of the intraocular pressure (IOP) lowering effect of
systemic Dexanabinol (HU-211), a non-psychotropic cannabinoid.J Ocul Pharmacol
Ther 16: 217-230.
Cooler, P. & Gregg, J.M. (1977) Effect of delta-9-tetrahydrocannabinol on
intraocular pressure. Southern Medical Journal 70: 951-954.
K, Roth M. (1982) Ocular effects of topical administration of delta-9- Tetrahydrocannabinol
in man. Archives of Ophthalmology 100:265-267.
K., Wynn, H., and Bowman, K.A (1978): A comparison of topical cannabinoids on
intraocular pressure. Exp. Eye Res. 27: 239246.
et al. (1994) The Health and Psychological Consequences of Cannabis Use,
Canberra, Australian Government Publishing Service 199.
R.S. & Frank, I.M. (1971) Marihuana smoking and intraocular pressure. J.Am.Med.Ass.
Hepler, R.S., Frank, I.M. & Petrus, R. (1976) Ocular effects of marihuana
smoking. In The Pharmacology of Marihuana ed. M.C. Braude & S. Szara.
Raven Press, New York, pp815-824.
of Medicine (1999) Marijuana and medicine: Assessing the science base.
National Academy Press
WM, Green K. (1983) Multiple-drop study of topically applied I % D9 Tetrahydrocannabinol
in human eyes. Archives of Ophthalmology 101 :591-593
L (1986) Health aspects of cannabis, Pharmacological Reviews, The American
Society for Pharmacology
and Experimental Therapeutics
Merritt, J.C., Crawford, W.J., Alexander, P.C., Anduze, A.L. & Gelbart, S.S.
(1980) Effect of marijuana on intraocular and blood pressure in glaucoma. Ophthalmology
Merritt, J.C., Olsen, J.L., Armstrong, J.R. & McKinnon, S.M. (1981) Topical
delta-9-tetrahydrocannabinol in hypertensive glaucomas. J. Pharm. Pharmacol.
Institutes of Health (1997) Workshop on the Medical Utility of Marijuana, Report
to the Director. Washington D.C.
et al. (2000) A submicron emulsion of HU-211, a synthetic cannabinoid, reduces
intraocular pressure in rabbits. Graefes Arch Clin Exp Opthalmol 238:
FW, Stark P. Jay WM, Schanzlin DJ. (1979) Nabilone: a pressure-reducing synthetic
benzopyran in open-angle glaucoma. Ophthalmology 86:156-160.
Perez-Reyez, M., Wagner, D., Wall, M.E. & Davis, K.H. (1976) Intravenous administration
of cannabinoids and intraocular pressure. In The Pharmacology of Marihuana
ed. M.C. Braude & S. Szara. Raven Press, New York, pp829-832.
JS, Shields MB, Weber PA, Crow JW, Cocchetto DM, Harris WA, Howes JF. (1981) Effect
of synthetic cannabinoids on elevated intraocular pressure. Ophthalmology
M.E., and Lockhart, A.B. (1980) The treatment of glaucoma using a nonpsychoactive
preparation of Cannabis sativa. West Indian Med. J. 29: 390.
E, Belkin M, Schwartz M. (1996) HU-211, a nonpsychotropic cannabinoid, produces
short- and long-term neuroprotection after optic nerve axotomy. Journal of
Colasanti, B.K. 1986. Review: Ocular hypotensive affect of marihuana cannabinoids:
correlate of central action or separate phenomenon. J. Ocular Pharmacology
B.K. et al., 1984. Ocular hypotension, ocular toxicity, and neurotoxicity in response
to marijuana extract and cannabidiol. Gen. Pharmacol. 15: 479.
B.K. et al., 1984. Intraocular pressure, ocular toxicity and neurotoxicity after
administration of delta-9-tetrahydrocannabinol or cannabichromene. Exp. Eye
Res. 38: 63.
B.K. et al., 1984. Intraocular pressure, ocular toxicity and neurotoxicity after
administration of cannabinol or cannabigerol. Exp. Eye Res. 39:
W. & Merritt, J.C., 1979. Effects of tetrahydrocannabinol on arterial and
intraocular hypertension. Int. J. Clin. Pharmacol. Biopharmacol. 17:
K. and McDonald, T.F., 1987. Ocular toxicology of marijuana: an update. J.
Toxicol.-Cut. and Ocular Toxicol. 6: 309-334.
M. et at., 1981. Physiologic observations in a controlled clinical trial of the
antiemetic effectiveness of 5, 10, and 15 mg of delta-9-tetrahydrocannabinol in
cancer chemotherapy: ophthalmologic implications. J. Clin. Pharmacol. 21:
J.C. et at., 1980. Oral delta-9-tetrahydrocannabinol in heterogenous glaucomas.
Ann. Opthalmol. 12: 8.
J.C. et at., 1981. Topical delta-9-tetrahydrocannabinol and aqueous dynamics in
glaucoma. J. Clin. Pharmacol. 21: 467S-471S.
J.C. et at., 1982. Topical delta-9-tetrahydrocannabinol as a potential glaucoma
agent. Glaucoma 4: 253-255.
D., 1974. The ocular manifestation of the cannabinoids. Ophthalmologia
a large collection of research materials, see our research
Youngs ruling - Docket 86-22
The US Drug Enforcement Agency held hearings
in 1987 to determine whether cannabis should be allowed as medicine. Doctors,
nurses, patients and academics testified that they had witnessed people using
cannabis as a medicine sucessfully. A part of the report is concerned with glaucoma,
and it makes astonishing reading.
Glaucoma Research Foundation is a non-profit
organisation dedicated to preserving sight. It includes a Glaucoma FAQ, factsheets
and more. It includes research news, but nothing about cannabis at the moment.
is a newsgroup, alt.support.glaucoma,
which occasionally has anecdotal references to cannabis, as well as other complementary
Glaucoma Home Page has a lot of interesting
information about the condition, including the glaucoma FAQ and discussions about
existing medications and side-effects. You can even use a form to send questions