CLINICAL
EFFECTS OF OLEORESIN CAPSICUM (PEPPER SPRAY) ON THE HUMAN CORNEA AND
CONJUNCTIVA.
Zollman
TM, Bragg RM, Harrison DA. Ophthalmology 2000 Dec;107(12):2186-9.
OBJECTIVE:
To evaluate the effects of oleoresin capsicum (OC) on the human cornea and
conjunctiva and to test the effectiveness of topical anesthetics for relief of
pain.
DESIGN:
Prospective, randomized clinical trial.
METHODS:
Forty-seven subjects were examined before and at 10 minutes and 1 hour after
exposure to pepper spray during a training exercise. Eleven subjects were
reexamined at 1 week after exposure. A short, subjective questionnaire was
given asking subjects to rate their pain, blurring of vision, and tearing.
After exposure, subjects were randomly given a placebo, a topical nonsteroidal
antiinflammatory agent, or a topical anesthetic.
MAIN
OUTCOME MEASURES: Visual acuity and corneal sensitivity with a Cochet-Bonnet
aesthesiometer (scale of 1-6 cm) was measured and the eyes were examined with a
portable slit lamp using fluorescein. Symptoms of pain, blurring of vision, and
tearing were recorded in a ranking of 0 to 10.
RESULTS:
Visual acuity was unaffected by exposure to pepper spray. Corneal sensitivity
was reduced from a pretest mean of 5.7 cm to a posttest mean of 0.6 cm 10
minutes after exposure. At 1 hour, the mean corneal sensitivity had recovered
to 2.9 cm. Twenty-one percent of eyes had evidence of punctate epithelial
erosions, but no corneal abrasions were found. All subjects reported
significant pain, blurring of vision, and tearing at 10 minutes that was much
improved by 1 hour. Topical flurbiprofen 0.03% improved symptoms in two of 11
subjects, whereas topical proparacaine hydrochloride 0.5% improved symptoms in
16 of 29 eyes. At 1 week after exposure, corneal sensation returned to
baseline, and no corneal abnormalities were noted.
CONCLUSIONS:
The predominant symptom after exposure to OC was pain. Topical flurbiprofen was
not helpful in reducing symptoms of exposure, whereas topical proparacaine was
effective in relieving pain in most subjects. Corneal sensitivity was
dramatically reduced at 10 minutes after exposure and was improved after 1
hour. At 1 week, corneal sensation had returned to normal, as had slit-lamp
appearance on all subjects examined.