Santonin (C15H18O3 = 244.29) is the lactone of santonic acid,,derived from the flower heads of Levant Wormseed (Artemisia pauciflora), a plant of Northern Turkestan and Russia.

Pharmacodynamics.

Central Nervous System. - Santonin is an irritating stimulant of the cortex and basal ganglia, and later of the synapses of the spinal cord.

Muscular System. - No direct action known.

Respiration is not altered until late, when asphyxia ensues from centric action.

Heart. - No alteration.

Blood-pressure. - No effect except in late acute poisoning, when there is a reflex fall from general collapse.

Eye. - Santonin alters the violet-sensitive substance in the retina, a xanthopsia resulting.

Alimentary Tract. - Mildly irritant.

Secretory glands are apparently not affected.

Metabolism. - No constant change noted.

Temperature not affected.

Absorption is very prompt by both stomach and intestines.

Local Action. - None.

Symptoms.

Therapeutic Doses.

Slightly bitter taste. Disturbance of color sense, violets being diminished and yellows accentuated.

Toxic Doses.

Unilateral twitching of head muscles.

Rolling of eyes.

Grinding of teeth.

Nausea and vomiting.

Confusion. Possible aphasia.

Epileptiform convulsions.

Coma and asphyxia.

Therapeutics.

Santonin is used for the expulsion of the round worm, Ascaris lumbricoides. The diet should be much restricted for the preceding 24 hours. Four hours after administering the drug, a full dose of castor oil should be given.

Dosage.

Santoninum, 0.03 to 0.1 Gm.

Trochisci Santonini, each contains 0.03 Gm. Santonin.

Quassia. - Infusions of Quassia are used to free the lower bowel of threadworms, being used in the form of enemata. It probably acts by stupefying the parasite.