An anthelmintic is a remedy designed to promote the death or expulsion of intestinal worms. Most of the remedies are also toxic to man, and since the anthelmintic is to attack the worm, rather than the patient, the dose must be as large as one dare risk, whether the patient is a child or an adult.

Before the administration of a toxic anthelmintic it is customary to starve the patient for from twelve to twenty-four hours and to give a brisk cathartic, the object being to clean out the intestines and leave the worm in an exposed condition. The dose is then administered, and is followed in four or five hours by a brisk, rapidly acting cathartic, such as castor oil or salts, to carry out the worm. Castor oil has been objected to on the ground that an oily medium will promote the absorption of the poison by the patient. This may be true, especially in the case of oleoresin of male fern, if rapid evacuation of the bowels does not take place. The different kinds of parasite require different kinds of treatment, as follows:

1. The Pin-Worms Or Thread-Worms (Oxyuris Vermicularis)

These are tiny, thread-like organisms which live in great abundance in the colon or the adjoining portion of the ileum, chiefly in the mucus. As they do not cling to the intestinal wall, they are readily carried out by cathartics; or, as they are very vulnerable, may be attacked by colon irrigations. Occasionally they penetrate the mucous membrane of the intestine or inhabit the appendix, and then they cannot be dislodged.

The cathartics mostly employed are calomel and castor oil. By mouth both thymol and oil of chenopodium, as used for hookworms, have proved highly effective. A number of substances are used for colon injection, viz., the infusion of quassia, lime-water, a solution of phenol, 0.25 per cent., a solution of quinine bisulphate, 1: 2000, a solution of tannic acid or alum, 30 grains (2 gm.) in one pint (480 c.c.), and soapsuds containing 1/2 ounce of the oil of turpentine to a quart. The astringents are effective not only by shriveling the worms, but also by lessening the intestinal mucus in which the worms may lodge. The Hymenolepis or Taenia nana, which are tiny tape-worms, are sometimes taken for pin-worms.

2. The Round-Worms

a. The common round-worm, Ascaris lumbricoides, grows to a length of 6 to 12 inches or even more. They usually inhabit the small intestine, but may be found in the colon or stomach, and have been known to stop up the common bile-duct. The author has had several patients who have vomited round-worms, and in two instances drew up a piece of round-worm through a stomach-tube. These must have been in the stomach. They may be the cause of intestinal hemorrhage. The remedies are:

Chenopodium - see under "Hookworms."

Santonin (santoninum), a glucoside from santonica (Levant wormseed), dose, 2 grains (0.12 gm.) for an adult, and 1 grain (0.06 gm.) for a child of five years. Santonica, 1/2 dram (2 gm.), is sometimes taken as it is or in the form of an infusion. Santonin is highly toxic, and death has occurred from 5 grains (0.3 gm.) in an adult, and 3 grains (0.2 gm.) in a child. The symptoms of poisoning are nausea, vomiting, and central stimulation. The reflexes are increased, and there may be headache, dizziness, delirium, hallucinations, and possibly epileptiform convulsions, followed by collapse and death. A peculiarity of santonin poisoning is partial blindness, accompanied by yellow vision. Baxter reports lost vision in a girl of five after 1/2 grain (0.03 gm.). Jelliffe (1906) reports prolonged convulsions, followed by collapse, in a girl, from two troches followed by castor oil which failed to move the bowels. After this she was blind, very restless, and prostrated for three weeks, and showed signs of nephritis. She became a permanent epileptic.

The treatment of poisoning is lavage of the stomach, followed by a large dose of Epsom salts, the inhalation of ether, and the management of symptoms as they arise. The central stimulation must be handled with care because of the tendency to collapse.

Santonin has come into notice of late as a remedy for the pains of locomotor ataxia and for diabetes, but clinical data do not justify these uses of so dangerous a drug.

Spigelia (pink-root) has an official fluidextract, dose, 60 minims, (4 c.c.). It is frequently given with senna (fluidextract of pink-root and senna), the senna furnishing the required, though rather late, cathartic action. In poisoning it causes central depression, with prostration, stupor or coma, muscular weakness, incoordination, and collapse.

b. The hookworms (Uncinaria or Necator or Ankylostoma americana) are treated by thymol or oil of chenopodium. Thymol - Public Health Bulletin No. 32 recommends a dose of Epsom salts at night, followed at 6 A. M. by half the dose of thymol, at 8 by the other half of the thymol, and at 10 by another dose of Epsom salts. This treatment is repeated once a week. The dose recommended is 7 1/2 grains (0.5 gm.) for a child of five years, and 45-60 grains (3 to 4 gm.) for an adult, given in 5-grain (0.3 gm.) capsules. It is best mixed with an equal weight of lactose or sodium bicarbonate. Seidell finds insignificant amounts of thymol in the feces and only 50 per cent. in the urine, He notes that absorption is not promoted by its solution in oil.

Thymol has also been employed in trichinosis, both while the parasites are still in the intestine and when they are lodged in the muscles. For the latter, 2 to 3 grains (0.12-0.2 gm.) in 30 to 45 minims (2-3 c.c.) of olive oil are injected subcutaneously daily. Musgrave recommends thymol for irrigation in amebic colitis. Thymol has in several instances caused fatal poisoning of the volatile oil type. Death has resulted from 15 grains (1 gm.) in a child; yet in adults as much as 225 grains (15 gm.) have been given in twelve hours (Bozzolo, 1912) without any toxic effects.