Aconitine (C34H47NO11 = 640.55) is an alkaloid derived from Aconitum napellus, or Monkshood, a perennial herb.

Pharmacodynamics.

Central Nervous System. - Marked stimulation of the medulla.

Muscular System. - Reflex weakness, secondary to the diminished circulation.

Respiration. - Aconite produces a slow, labored breathing, probably due to vagus action, both centric and peripheral.

Heart is markedly slowed by centric action; later, in toxic doses, the heart is accelerated by paralysis of the inhibitory terminals and by local irritation of the heart muscle.

Blood-pressure falls from lessened heart output, and perhaps somewhat from centric action.

Eye. - Pupil contracted on local application.

Alimentary Tract. - Numbing sensation; sometimes centric vomiting.

Secretory Glands. - Salivary glands reflexly active from stimulation of oral ter-minants; sweat-glands may be irritated.

Metabolism. - Not affected.

Temperature falls; cause unknown, but it is assumed to be due to direct action on the thermic center.

Absorption. - Medicinal effect is noted in about twenty minutes; continues for about five hours.

Excretion is mainly by urine; minutely in bile and saliva.

Local Action. - Irritates, later benumbs, sensory terminations.

Symptoms.

Therapeutic Doses.

Tingling of lips, tongue, and throat. Slight muscular weakness. Diminished force and frequency of heart.

Toxic Doses.

Prickling of throat, stomach, and skin. Salivation. Slow, feeble pulse, later becoming weak, rapid, and thready. Slow, shallow, labored breathing. Violent nausea and purging. Pale, cold, clammy skin. Great prostration Unimpaired intelligence. Respiratory failure.

Therapeutics.

Aconite may be used in strong adults as a circulatory sedative in the early stages of sthenic types of inflammations. Also as a local application to exposed nerves in toothache.

Dosage.

Fluidextractum Aconiti, 0.03 to 0.12 mil. Tinctura Aconiti, 0.3 to 2 mils. Aconitina, 0.00016 to 0.00032 Gm. Aconitina should be used with great circumspection, and never administered to children.

Aconitine 75

Crimson = stimulation. Violet = depression.