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352 DENTAL MEDICINE.
count of the delicacy of the conjunctiva, which it readily pene-
trates, and thus paralyzes the peripheral nerve-endings. The
anaesthesia is produced in from one to five minutes according to
the strength of the solution used, and is accompanied by marked
dilatation of the pupil. Applied to the peripheral sensory nerves it
paralyzes them ; its action is manifested first upon the sensitive
fibres and then upon the motor fibres. Poisonous doses of
cocaine cause convulsions of cerebral origin, both clonic and
tetanic. Taken internally cocaine stimulates the muscles, in-
creasing muscular povver temporarily, especially after starvation
or fatigue. It acts as a stimulant to the heart and circulation in
moderate doses, and also as a povtrerful respiratory stimulant, and
in poisonous doses it destroys life by failure of the respiration
with exhaustion from the convulsions. Cocaine increases the
bodily temperature if given in large doses, due to an increase of
heat-production ; but in moderate doses it has no such effect.
Cocaine is eliminated by the kidneys, but is chiefly dissipated
by oxidation in the body.
Therapeutic Uses.—Cocaine is an efficient local anaesthetic in
all cases where it can come in contact with the nerve filaments
in sufficient concentration. It is also employed in some forms of
insanity, melancholia, neurasthenia, gastralgia and in wasting dis-
eases, pruritic skin affections and hoarseness. The leaves in
cigarettes have relieved hay fever and throat affections. Cocaine
is employed as a local anaesthetic and local anodyne in all painful
affections of the eye, the operation for cataract, etc., but the
evidence as to its reliability in such deep operations as iridectomy,
squint, etc., is conflicting. (There are, however, cases reported
by Dr. Konigstein of even the surfaces of the eyelids entirely
losing their sensitiveness when hydrochlorate of cocaine was ap-
plied in solid form.) It is also employed in painful affections of
the pharynx and larynx, or of any other excitable mucous mem-
brane or of nerve tissue. Prof. Engle reports a case of trigeminal
neuralgia successfully treated by hypodermic injections of the
hydrochlorate of cocaine. Dr. Wagner, of Vienna, basing a
theory upon the established principle that fluids move from the
positive to the negative pole in a galvanic current, saturated the