American Materia Medica, Therapeutics and Pharmacognosy

Ergot is prepared by special processes of purification for hypodermic
injection. So used it is immediate in its action and can be so
administered when impossible to give it by the stomach. Ergotine in
solution in water and glycerine, is excellent for hypodermic
administration.
Physiological Action—Ergot causes both acute and chronic poisoning
when taken in toxic closes. Acute ergotism is characterized by vomiting,
purging, headache, dizziness, drowsiness, slowing of the pulse, dilatation
of the pupils, dyspnea, pain in the chest and loins, confusion of the
senses, formication, coldness, anesthesia, convulsions, swelling of the
face. Chronic ergotism is characterized by neuralgic pains, formication
and numbness of the extremities, opisthotonos, violent delirium
succeeded by exhaustion, death occurring in coma or in convulsions; or
the drug may affect nutrition; muscular weakness is followed by
gangrene of the limbs or superficial parts, which become blackened,
shriveled and hard—a dry gangrene, generally ending fatally.
Ergot is classed as a motor excitant by most writers, and yet the
evidences, as above described, of its depressing influence upon the
nervous system and upon the circulation are most conspicuous. In its
influence upon the circulation of the brain and spinal cord, it may be
given in sufficient doses to produce anemia, and that it does greatly
reduce the excitability of the nervous system, under certain
circumstances, none will deny. It acts in perfect harmony with the
bromides when there is acute cerebral engorgement with great nervous
excitability.
There is no doubt that it produces contraction of the arterioles, although
there are many evidences to prove that it may permit the venous
capillaries to dilate freely.
In its influence upon unstriped muscular fiber the action of ergot is
pronounced. It acts upon the muscular structure of the womb, producing
extreme tonic or tetanic spasm of the fibrillae, causing a marked
reduction in the size of the organ if enlarged, and rapid emptying of its
blood vessels, and consequent anemia. Many prominent writers believe
the anemia induced, causes the profound muscular contraction. It is
more plainly apparent that a peculiar irritating influence of the agent
upon such muscular structure induces its contraction, and that such
contraction, assisted by the influence of the agent upon the coats of the
arterioles, causes them to become emptied to a marked extent, and thus
Ellingwood’s American Materia Medica, Therapeutics and Pharmacognosy - Page 197