Jacob Bell
New Member
MERTON C. FLOM, ANTHONY J.
ADAMS, AND REESE T. JONES.
Normal pressure within the human eye was reduced
after smoking a socially relevant dose of
marijuana (12 mg. &9-tetrahydrocannabinol), but
only for light to moderate users who experienced
a substantial "high" and a state of peaceful relaxation
from the experimental dose. Analysis
suggests an indirect effect of the drug associated
with relaxation–a psychophysiologic state that
can be produced by drug and nondrug means.
Marijuana has been reported to reduce the
pressure within the human eye.' The normal
intraocular pressure (IOP) of about 15 mm. Hg
was found to drop after smoking IS mg. of
^"-tetrahydrocannabinol (AD-THC). This result
apparently led to the experimental use of marijuana
in a patient with glaucoma for whom the
abnormally high IOP dropped from a presmoke
level of 29 mm. Hg to 17 mm. Hg about 45
minutes after smoking; the treatment effect lasted
more than 4 hours.- Although the mechanism of
the drug action in reducing IOP is not yet understood,
there is interest11 in using marijuana for
the treatment of glaucoma.
Our experiments on the influence of marijuana
and other drugs on several vision functions included
measurements of IOP. We found marked
individual differences in the IOP changes after
smoking marijuana. IOP decreased only in those
subjects whose experience was limited to moderate
use and for whom the experimental dose
produced a substantial "high" and peaceful relaxation.
These results have implications for the
possible therapeutic use of marijuana, and suggest
a nondmg mechanism in the control of elevated
IOP.
Methods. Fifteen young male adults (18 to 30
years of age) experienced in smoking marijuana
participated in the IOP phase of the study. Their
experience ranged from smoking an average of
one cigarette per month to an average of several
per day. These paid volunteer subjects were
instructed to take no drugs (including alcohol)
for 24 hours before the experiment and to eat a
light, low-fat breakfast on the day of the tests.
Food and fluid intake during the experiments was
controlled. The experiments were conducted double-
blind with marijuana and marijuana placebo
being given on alternate experimental days.
IOP measurements were obtained following
instillation of one drop of 0.5 per cent ophthalmic
solution of proparacaine hydrochloride onto the
cornea. A Mackay-Marg tonometer was used for
all IOP measurements and a Coldmann tonometer
at some trials for comparison. After several trials
to establish the presmoke IOP baseline, the subject
smoked a 0.8 Cm. cigarette that contained
either marijuana placebo material or natural
marijuana plant material with 12 mg. THC, a
socially relevant dose. The cigarette was smoked
in the subject's usual style in about 10 minutes.
Results. The mean IOP before smoking marijuana
was 14.6 mm. Hg (S.D. = 2.3); before
smoking placebo it was 15.2 mm. Hg (S.D. =
2.6). The time courses of IOP for the marijuana
and placebo treatments are shown for the group
as a whole in Fig. 1. (The placebo curve was
displaced downward to equate the mean presmoke
IOP values.) It is seen that the average
IOP dropped more after smoking marijuana than
placebo. The greatest mean drop in IOP for the
group occurred 80 minutes alter marijuana (mean
= 2.1 mm. Hg, S.D. = 2.0). For placebo it
occurred 30 minutes after smoking (mean = 0.6
mm. Hg, S.D. = 2.1). What is important in
this experiment is how much the subjects' IOP
changed alter smoking marijuana compared to
the change after smoking placebo. Analysis ot
the data was performed with the Walsh test, a
nonparameti ie statistic designed for two related
samples of small size (N = 4 to 15). With this
test it was determined that the marijuana-induced
IOP changes relative to the placebo-induced IOP
changes were not significant at the 0.05 level
at any of the measurement times except at 80
minutes postsmoke where the relative IOP decrease
was significant at the 0.01 level. Thus,
while the mean relative IOP drop 80 minutes
alter smoking marijuana was small, the chances
that it could have occurred by chance are less
than 1 in 100. At 80 minutes after smoking, when
IOP for the marijuana treatment was at its minimum,
the radial pulse rate for the group had
declined to its presmoke level but the subjects'
average "high" rating was still at about 70 per
cent of its maximum (Fig. 1).
Only 7 out of 15 subjects exhibited a clear
decline in IOP after marijuana. These subjects
appeared less anxious, more relaxed, and more
sleepy during the experiment than the subjects
who had little or no IOP drop. An item analysis
was performed on the responses to a Subjective
Drug Effects Questionnaire (SDEQ) given to
each subject at the end of the day's trials. Subjects
with greater-than-mean IOP drop after
marijuana reported the following symptoms significantly
more often (p < 0.03 by the Fisher
exact probability test) than did subjects with
less-than-mean pressure drop: thinking seemed
fuzzier, eyes felt as if closed, arms or legs felt
weaker, felt more at peace with the world, felt
dopey, and thoughts moved slower. Other related
symptoms checked more often by subjects
with above-average IOP drop were: felt pleasantly
tired and sleepy (p = 0.08) and felt sleepier
(p = 0.12).
Correlational analysis was performed on postmarijuana
IOP change and several relevant variables
(Table I). Two points deserve mention.
First, IOP change is independent of pulse-rate
increment, but it is positively related to the
maximum "high " rating and to the score on the
6-iteni SDEQ scale pertaining to peaceful relaxation
and tiredness. Second, amount of marijuana
experience is inversely related to IOP
drop and to both subjective measures (maximum
"high " rating and the 6-item SDEQ score); marijuana
experience is independent of pulse increase.
Blood plasma concentration of A"-THC has
been reported by Calanter and co-workers4 to be
highly correlated with increase in pulse rate. Dose
of smoked marijuana has been found to be related
to heart rate increase.ft Volavka and coworkers'
1 believe heart rate increase is so closely
related to marijuana dose that it can be used
as a bioassay of THC. To the extent that the
reported relationship between blood THC and
pulse rate holds in our sample, IOP drop would
be independent of plasma THC concentration.
In any case, IOP drop in our subjects is related
more to the subjective effects of smoking marijuana
than to the increase in pulse rate.
Tolerance to certain marijuana effects is indicated
from our results (Table I). Individuals who
used marijuana the most tended to have little
or no IOP drop (rs = -0.61), and reported few
drug-induced symptoms of peaceful relaxation and
tiredness (rH = -0.78). Subjects who used marijuana
at least four times per week and stayed
"stoned" all day on about half the smoking
occasions (Table I, subjects 007 and 015) exhibited
little or no IOP drop; of nine subjects
with less than this usage, seven exhibited a clear
drop in IOP (Table I, first seven subjects). Also,
the "high " ratings of the more frequent users
was lower than those for less experienced users
(rs = -0.61) which, however, may be attributed
to a scaling factor since a rating of 100 is defined
as the "highest" a subject has ever felt
after smoking marijuana.
Discussion. The mechanism by which marijuana
reduces IOP is not understood. Green and Pedersoiv
applied THC directly to the excised ciliary
body of rabbit and found a pronounced decrease
in fluid secretion and increase in ultrafiltration.
Of these two changes, only the decreased secretion
is consistent with the marijuana-induced IOP
drop they observed in rabbit. For man, they emphasized
that, "if, however, one accepts the view
that ultrafiltration is the most important process
in aqueous formation . . . then one must look
elsewhere for a suitable explanation."7
Blood pressure changes are not likely to have
produced the IOP decreases that occurred in our
subjects after smoking marijuana cigaretttes containing
12 mg. THC (1.5 per cent THC). Marijuana
research has consistently shown no significant
changes in blood pressure in man following
intake of low to moderate doses (such as we
used) and ordy a slight increase with doses of
2.9 per cent. HolUsters has reported blood pressure
reducing effects of THC only at doses so
high as to produce severe mental effects in man.
Our THC closes were far below these high levels,
and probably induced no changes in blood pressure
that could account for the IOP decreases.
In our study, the observed decrease in IOP
in 7 out of 15 subjects could have resulted from
a direct effect of marijuana on the ocular fluid
dynamics. On the other hand, part of the marijuana-
induced IOP drop may have been an
epiphenomenon or secondary effect associated with
the subjective state created by the drug. Indeed,
we found that "high" rating and the 6-item SDEQ
(relaxation) score were significantly correlated
with IOP drop, and we conjectured from pulserate
analysis that blood THC was probably not
associated with the observed IOP decreases.
The idea that IOP can lie reduced through
changes in the psychophysiological state of the
subject is supported by reports of IOP decline
following exercise,11 by the successful treatment
of primary glaucoma at health resorts that emphasize
therapeutic exercise and mineral baths,1"
and by the clinical observation that some glaucoma
patients show substantially lowered IOP
after a clay of hospital bed rest with no change
in therapeutic drug usage. Moreover, the IOP
drop following ingestion of ethyl alcohol has a
longer duration (about 4 hours) than can be
accounted for on the basis of rapid change in
blood osmotic pressure or suppression of the antidiuretic
hormone.11 Perhaps the relatively prolonged
IOP decline is related to the sustained relaxing
effect of alcohol. In pilot experiments with
chlordiazepoxide hydrochloride (an anti-anxiety
and muscle-relaxing drug with no known diuretic
properties), we found that a 50 mg. dose
produced an IOP drop of about 5 mm. Hg lasting
about 3 hours in each of three normal subjects.
Social use of marijuana, particularly in relatively
inexperienced users, may lead to unusually
low IOP. Several of our subjects had post-marijuana
IOP measurements as low as 7 or 8 mm.
Hg. Therapeutic use of marijuana for the treatment
of glaucoma seems premature considering the
present state of knowledge of the drug's action.
Our results suggest an indirect effect of the
drug associated with relaxation and tiredness–a
psychophysiological state that can be produced
by drug and nondrug means. However, heavy use
of marijuana appears to prevent an IOP drop
after smoking the drug. If IOP can be reduced
by marijuana, alcohol, or chlordiazepoxide (drugs
which tend to produce relaxation) as well as by
nondrug means such as mild exercise, mineral
baths, or hospital rest, then it seems legitimate
to propose that the search for means of controlling
or preventing high IOP should include the possible
role of relaxation.
From the Smith-Kettlewell Institute of Visual
Sciences, Pacific Medical Center, San Francisco,
and the University of California (School of
Optometry, Berkeley; School of Medicine, San
Francisco). This study was supported in part by
contracts (DADA17-72-C-2083 and DADA17-73-
C-3106) from the United States Army Medical
Research and Development Command to the
Visual Sciences Division of the Optical Sciences
Croup, San Rafael, Calif., and by a grant from
the National Institutes of Health '( MH15842) to
Dr. Jones. Submitted for publication May 21,
1974. Reprint requests: Dr. M. C. Floni, School
of Optometry, University of Californila, Berkeley,
Calif. 94720.
Key words: marijuana, intraocular pressure, relaxation,
alcohol, trancjuilizer, socially used drugs,
tonometry, tetrahydrocannabinol, glaucoma, chlordiazepoxide
hydrochloride.
REFERENCES
1. Hepler, R. S., and Frank, I. R.: Marijuana
smoking and intraocular pressure, |. A. M. A.
217: 1392, 1971.
2. Hepler, R. S., Frank, I. M., and Ungerleider,
J. T.: Marijuana smoking and intraocular pressure
in young adults, Paper presented at the
meeting of the Association for Research in
Vision and Ophthalmology, Sarasota, Fla.,
April 26, 1972.
3. Shapiro, D.: The ocular manifestations of
the cannabinols, Ophthalmologica 1C8: 366,
1974.
4. Calanter, M., Wyatt, R. J., Lemberger, L.,
et al.: Effects on humans of A'J-tetrahydrocannabinol
administered by smoking, Science
176: 934, 1972.
5. Johnson, S., and Domino, E. F.: Some cardiovascular
effects of marijuana smoking in normal
volunteers, Clin. Pharmacol. Ther. 12:
762, 1971.
6. Volavka, J., Crown, P., Dombush, R., et al.:
EEC, heart rate, and mood change ("high")
after cannabis, Psychopharmacologia 32: 11,
1973.
7. Green, K., and Pederson, J. E.: Effect of A1-
tetrahydrocannabinol on aqueous dynamics
and ciliary body permeability in the rabbit,
Exp. Eye Res. 15: 499, 1973.
8. Hollister, L. E.: Marijuana in man: three
years later, Science 172: 21, 1971.
9. Leighton, D. A., and Phillips, C. I.: Effect
of moderate exercise on the ocular tension,
Br. J. Ophthalmol. 54: 599, 1970.
10. Mayachenkova, E. V.: Claucoma treatment
at the eye department of the "Picket" Sanatorium,
Vest. Oftal'mol. 83: 91, 1970.
11. Houle, R. E., and Grant, W. M.: Alcohol,
vasopressin, and intraocular pressure, INVEST.
OPHTHALMOL. 6: 145, 1967.
Source: Marijuana smoking and reduced pressure in human eyes: drug action or epiphenomenon?
ADAMS, AND REESE T. JONES.
Normal pressure within the human eye was reduced
after smoking a socially relevant dose of
marijuana (12 mg. &9-tetrahydrocannabinol), but
only for light to moderate users who experienced
a substantial "high" and a state of peaceful relaxation
from the experimental dose. Analysis
suggests an indirect effect of the drug associated
with relaxation–a psychophysiologic state that
can be produced by drug and nondrug means.
Marijuana has been reported to reduce the
pressure within the human eye.' The normal
intraocular pressure (IOP) of about 15 mm. Hg
was found to drop after smoking IS mg. of
^"-tetrahydrocannabinol (AD-THC). This result
apparently led to the experimental use of marijuana
in a patient with glaucoma for whom the
abnormally high IOP dropped from a presmoke
level of 29 mm. Hg to 17 mm. Hg about 45
minutes after smoking; the treatment effect lasted
more than 4 hours.- Although the mechanism of
the drug action in reducing IOP is not yet understood,
there is interest11 in using marijuana for
the treatment of glaucoma.
Our experiments on the influence of marijuana
and other drugs on several vision functions included
measurements of IOP. We found marked
individual differences in the IOP changes after
smoking marijuana. IOP decreased only in those
subjects whose experience was limited to moderate
use and for whom the experimental dose
produced a substantial "high" and peaceful relaxation.
These results have implications for the
possible therapeutic use of marijuana, and suggest
a nondmg mechanism in the control of elevated
IOP.
Methods. Fifteen young male adults (18 to 30
years of age) experienced in smoking marijuana
participated in the IOP phase of the study. Their
experience ranged from smoking an average of
one cigarette per month to an average of several
per day. These paid volunteer subjects were
instructed to take no drugs (including alcohol)
for 24 hours before the experiment and to eat a
light, low-fat breakfast on the day of the tests.
Food and fluid intake during the experiments was
controlled. The experiments were conducted double-
blind with marijuana and marijuana placebo
being given on alternate experimental days.
IOP measurements were obtained following
instillation of one drop of 0.5 per cent ophthalmic
solution of proparacaine hydrochloride onto the
cornea. A Mackay-Marg tonometer was used for
all IOP measurements and a Coldmann tonometer
at some trials for comparison. After several trials
to establish the presmoke IOP baseline, the subject
smoked a 0.8 Cm. cigarette that contained
either marijuana placebo material or natural
marijuana plant material with 12 mg. THC, a
socially relevant dose. The cigarette was smoked
in the subject's usual style in about 10 minutes.
Results. The mean IOP before smoking marijuana
was 14.6 mm. Hg (S.D. = 2.3); before
smoking placebo it was 15.2 mm. Hg (S.D. =
2.6). The time courses of IOP for the marijuana
and placebo treatments are shown for the group
as a whole in Fig. 1. (The placebo curve was
displaced downward to equate the mean presmoke
IOP values.) It is seen that the average
IOP dropped more after smoking marijuana than
placebo. The greatest mean drop in IOP for the
group occurred 80 minutes alter marijuana (mean
= 2.1 mm. Hg, S.D. = 2.0). For placebo it
occurred 30 minutes after smoking (mean = 0.6
mm. Hg, S.D. = 2.1). What is important in
this experiment is how much the subjects' IOP
changed alter smoking marijuana compared to
the change after smoking placebo. Analysis ot
the data was performed with the Walsh test, a
nonparameti ie statistic designed for two related
samples of small size (N = 4 to 15). With this
test it was determined that the marijuana-induced
IOP changes relative to the placebo-induced IOP
changes were not significant at the 0.05 level
at any of the measurement times except at 80
minutes postsmoke where the relative IOP decrease
was significant at the 0.01 level. Thus,
while the mean relative IOP drop 80 minutes
alter smoking marijuana was small, the chances
that it could have occurred by chance are less
than 1 in 100. At 80 minutes after smoking, when
IOP for the marijuana treatment was at its minimum,
the radial pulse rate for the group had
declined to its presmoke level but the subjects'
average "high" rating was still at about 70 per
cent of its maximum (Fig. 1).
Only 7 out of 15 subjects exhibited a clear
decline in IOP after marijuana. These subjects
appeared less anxious, more relaxed, and more
sleepy during the experiment than the subjects
who had little or no IOP drop. An item analysis
was performed on the responses to a Subjective
Drug Effects Questionnaire (SDEQ) given to
each subject at the end of the day's trials. Subjects
with greater-than-mean IOP drop after
marijuana reported the following symptoms significantly
more often (p < 0.03 by the Fisher
exact probability test) than did subjects with
less-than-mean pressure drop: thinking seemed
fuzzier, eyes felt as if closed, arms or legs felt
weaker, felt more at peace with the world, felt
dopey, and thoughts moved slower. Other related
symptoms checked more often by subjects
with above-average IOP drop were: felt pleasantly
tired and sleepy (p = 0.08) and felt sleepier
(p = 0.12).
Correlational analysis was performed on postmarijuana
IOP change and several relevant variables
(Table I). Two points deserve mention.
First, IOP change is independent of pulse-rate
increment, but it is positively related to the
maximum "high " rating and to the score on the
6-iteni SDEQ scale pertaining to peaceful relaxation
and tiredness. Second, amount of marijuana
experience is inversely related to IOP
drop and to both subjective measures (maximum
"high " rating and the 6-item SDEQ score); marijuana
experience is independent of pulse increase.
Blood plasma concentration of A"-THC has
been reported by Calanter and co-workers4 to be
highly correlated with increase in pulse rate. Dose
of smoked marijuana has been found to be related
to heart rate increase.ft Volavka and coworkers'
1 believe heart rate increase is so closely
related to marijuana dose that it can be used
as a bioassay of THC. To the extent that the
reported relationship between blood THC and
pulse rate holds in our sample, IOP drop would
be independent of plasma THC concentration.
In any case, IOP drop in our subjects is related
more to the subjective effects of smoking marijuana
than to the increase in pulse rate.
Tolerance to certain marijuana effects is indicated
from our results (Table I). Individuals who
used marijuana the most tended to have little
or no IOP drop (rs = -0.61), and reported few
drug-induced symptoms of peaceful relaxation and
tiredness (rH = -0.78). Subjects who used marijuana
at least four times per week and stayed
"stoned" all day on about half the smoking
occasions (Table I, subjects 007 and 015) exhibited
little or no IOP drop; of nine subjects
with less than this usage, seven exhibited a clear
drop in IOP (Table I, first seven subjects). Also,
the "high " ratings of the more frequent users
was lower than those for less experienced users
(rs = -0.61) which, however, may be attributed
to a scaling factor since a rating of 100 is defined
as the "highest" a subject has ever felt
after smoking marijuana.
Discussion. The mechanism by which marijuana
reduces IOP is not understood. Green and Pedersoiv
applied THC directly to the excised ciliary
body of rabbit and found a pronounced decrease
in fluid secretion and increase in ultrafiltration.
Of these two changes, only the decreased secretion
is consistent with the marijuana-induced IOP
drop they observed in rabbit. For man, they emphasized
that, "if, however, one accepts the view
that ultrafiltration is the most important process
in aqueous formation . . . then one must look
elsewhere for a suitable explanation."7
Blood pressure changes are not likely to have
produced the IOP decreases that occurred in our
subjects after smoking marijuana cigaretttes containing
12 mg. THC (1.5 per cent THC). Marijuana
research has consistently shown no significant
changes in blood pressure in man following
intake of low to moderate doses (such as we
used) and ordy a slight increase with doses of
2.9 per cent. HolUsters has reported blood pressure
reducing effects of THC only at doses so
high as to produce severe mental effects in man.
Our THC closes were far below these high levels,
and probably induced no changes in blood pressure
that could account for the IOP decreases.
In our study, the observed decrease in IOP
in 7 out of 15 subjects could have resulted from
a direct effect of marijuana on the ocular fluid
dynamics. On the other hand, part of the marijuana-
induced IOP drop may have been an
epiphenomenon or secondary effect associated with
the subjective state created by the drug. Indeed,
we found that "high" rating and the 6-item SDEQ
(relaxation) score were significantly correlated
with IOP drop, and we conjectured from pulserate
analysis that blood THC was probably not
associated with the observed IOP decreases.
The idea that IOP can lie reduced through
changes in the psychophysiological state of the
subject is supported by reports of IOP decline
following exercise,11 by the successful treatment
of primary glaucoma at health resorts that emphasize
therapeutic exercise and mineral baths,1"
and by the clinical observation that some glaucoma
patients show substantially lowered IOP
after a clay of hospital bed rest with no change
in therapeutic drug usage. Moreover, the IOP
drop following ingestion of ethyl alcohol has a
longer duration (about 4 hours) than can be
accounted for on the basis of rapid change in
blood osmotic pressure or suppression of the antidiuretic
hormone.11 Perhaps the relatively prolonged
IOP decline is related to the sustained relaxing
effect of alcohol. In pilot experiments with
chlordiazepoxide hydrochloride (an anti-anxiety
and muscle-relaxing drug with no known diuretic
properties), we found that a 50 mg. dose
produced an IOP drop of about 5 mm. Hg lasting
about 3 hours in each of three normal subjects.
Social use of marijuana, particularly in relatively
inexperienced users, may lead to unusually
low IOP. Several of our subjects had post-marijuana
IOP measurements as low as 7 or 8 mm.
Hg. Therapeutic use of marijuana for the treatment
of glaucoma seems premature considering the
present state of knowledge of the drug's action.
Our results suggest an indirect effect of the
drug associated with relaxation and tiredness–a
psychophysiological state that can be produced
by drug and nondrug means. However, heavy use
of marijuana appears to prevent an IOP drop
after smoking the drug. If IOP can be reduced
by marijuana, alcohol, or chlordiazepoxide (drugs
which tend to produce relaxation) as well as by
nondrug means such as mild exercise, mineral
baths, or hospital rest, then it seems legitimate
to propose that the search for means of controlling
or preventing high IOP should include the possible
role of relaxation.
From the Smith-Kettlewell Institute of Visual
Sciences, Pacific Medical Center, San Francisco,
and the University of California (School of
Optometry, Berkeley; School of Medicine, San
Francisco). This study was supported in part by
contracts (DADA17-72-C-2083 and DADA17-73-
C-3106) from the United States Army Medical
Research and Development Command to the
Visual Sciences Division of the Optical Sciences
Croup, San Rafael, Calif., and by a grant from
the National Institutes of Health '( MH15842) to
Dr. Jones. Submitted for publication May 21,
1974. Reprint requests: Dr. M. C. Floni, School
of Optometry, University of Californila, Berkeley,
Calif. 94720.
Key words: marijuana, intraocular pressure, relaxation,
alcohol, trancjuilizer, socially used drugs,
tonometry, tetrahydrocannabinol, glaucoma, chlordiazepoxide
hydrochloride.
REFERENCES
1. Hepler, R. S., and Frank, I. R.: Marijuana
smoking and intraocular pressure, |. A. M. A.
217: 1392, 1971.
2. Hepler, R. S., Frank, I. M., and Ungerleider,
J. T.: Marijuana smoking and intraocular pressure
in young adults, Paper presented at the
meeting of the Association for Research in
Vision and Ophthalmology, Sarasota, Fla.,
April 26, 1972.
3. Shapiro, D.: The ocular manifestations of
the cannabinols, Ophthalmologica 1C8: 366,
1974.
4. Calanter, M., Wyatt, R. J., Lemberger, L.,
et al.: Effects on humans of A'J-tetrahydrocannabinol
administered by smoking, Science
176: 934, 1972.
5. Johnson, S., and Domino, E. F.: Some cardiovascular
effects of marijuana smoking in normal
volunteers, Clin. Pharmacol. Ther. 12:
762, 1971.
6. Volavka, J., Crown, P., Dombush, R., et al.:
EEC, heart rate, and mood change ("high")
after cannabis, Psychopharmacologia 32: 11,
1973.
7. Green, K., and Pederson, J. E.: Effect of A1-
tetrahydrocannabinol on aqueous dynamics
and ciliary body permeability in the rabbit,
Exp. Eye Res. 15: 499, 1973.
8. Hollister, L. E.: Marijuana in man: three
years later, Science 172: 21, 1971.
9. Leighton, D. A., and Phillips, C. I.: Effect
of moderate exercise on the ocular tension,
Br. J. Ophthalmol. 54: 599, 1970.
10. Mayachenkova, E. V.: Claucoma treatment
at the eye department of the "Picket" Sanatorium,
Vest. Oftal'mol. 83: 91, 1970.
11. Houle, R. E., and Grant, W. M.: Alcohol,
vasopressin, and intraocular pressure, INVEST.
OPHTHALMOL. 6: 145, 1967.
Source: Marijuana smoking and reduced pressure in human eyes: drug action or epiphenomenon?
