B. To relax over contracted smooth muscle - as in spasmodic asthma and the spasm of smooth muscle which results in colic.

The latter occurs in the esophagus, cardia (cardiospasm), pylorus (pylorospasm), ileocecal valve, or any part of the stomach or intestine, in the bile-passages or gall-bladder (biliary colic), in the pelvis of the kidney or ureter (renal colic), in the neck of the bladder, and in spasmodic dysmenorrhea (in this last mentioned the drug may be of little use because of the congestive condition). Atropine or extract of belladonna may be added to irritant cathartics as a corrective to prevent griping.

In the obstipation which occurs in lead-poisoning and in local peritoneal irritation (as in appendicitis, salpingitis, or ovaritis, or renal or biliary colic) atropine may overcome the reflex spasm with resultant catharsis. In intestinal obstruction from suspected spasm, or in fecal impaction, a large dose, 1/13 grain (0.005 gm.), has been recommended. But when there is a real surgical obstruction, such a procedure serves only to delay operation, and sometimes with fatal result.

C. To depress the sensory nerve-endings - to allay itching (the liniment); to lessen pain, as in ulcer of the leg, anal fissure, or projecting hemorrhoids (the ointment); and the drug by mouth for irritable bladder or urethra, as in cystitis and urethritis, and in enuresis nocturna.

D. In the eye - as a mydriatic, cycloplegic and analgesic, for the following purposes:

1. To facilitate examination of the internal eye posterior to the pupil.

2. To paralyze accommodation in fitting glasses.

3. In inflammatory conditions of either external or internal eye, to give rest to iris and ciliary muscle, to lessen pain, and to prevent the spread of the inflammation to the iris; and in iritis, to prevent the formation of adhesions to the lens or cornea, or to rupture newly formed adhesions. It is employed in 1/2 to 1 per cent. solution, and takes a long while for full dilatation. As the dilatation of the pupil and paralysis of accommodation last several days, atropine is especially useful in the inflammatory conditions; while for examinations and fitting glasses more rapidly acting drugs are preferred. After the continued use, for a few days, the return to normal may be delayed for twelve to fourteen days (de Schweinitz), but the restoration may be greatly hastened by the use of phy-sostigmine. In a recent symposium (1916) prominent American oculists agreed that, to avoid the risk of glaucoma, phy-sostigmine should regularly be employed after the use of atropine or homatropine. De Schweinitz says that in the use of atropine to correct errors of refraction one drop should be dropped into the eye three times during the day preceding the examination; and in hypermetropic eyes, especially those with spasm of accommodation, the drug should be used for several days before the examination for refractive errors.

E. In certain spasmodic nervous conditions, as in whooping-cough (perhaps enuresis nocturna under this head).

F. In exophthalmic goiter (hyperthyroidism) it probably acts by decreasing the glandular secretion. (Sollmann states that atropine is antagonistic to thyroiodin.) Bromides should be given at the same time, as the cerebral effects of belladonna are undesirable in this disease.

G. As preliminary to general anesthesia - here it is of use to check excessive secretion in mouth and respiratory passages, to stimulate the respiratory center, and in chloroform anesthesia to prevent excessive reflex vagus stimulation at the onset.

H. To stimulate respiration, as in general anesthesia, in pneumonia, or in collapse from narcotic drugs; to prevent respiratory depression, as when given with morphine.

I. To check excessive vagus action, as in the excessive inhibition stage of chloroform anesthesia, and in vagus bradycardia or partial heart-block from disease or from a drug of the digitalis group. It has no value in complete and permanent heart-block. In many human experiments with hypodermatic doses the author was unable to get vagus effects with less than 1/65 grain (1 gm.). The effects last not more than an hour. Thomas Lewis (1911) says that "atropine has never been known to abolish the whole hindrance to conduction."

J. In anaphylaxis, as in serum sickness. In experiments on guinea-pigs sensitized with horse-serum, Auer (1910) reports that without atropine 75 per cent. died, and with atropine only 28 per cent. died.

All the drugs of the group, viz., belladonna, scopola, stramonium, and hyoscyamus, have actions of the atropine type, and can be used interchangeably for the ordinary peripheral effects.

A special use of the stramonium leaves is in spasmodic asthma, in which condition smoke of the burning leaves is inhaled. The leaves may be burned in a saucer, either alone or with other drugs, or impregnated with potassium nitrate (that is, saturated with a solution of potassium nitrate and then dried); or they may be added to tobacco, lobelia, or cubebs, and made into cigars or cigarettes to be smoked at the time of the attack. The leaves of belladonna will serve as well as those of stramonium.

The chief use of hyoscyamus is as a sedative in irritable bladder, cystitis, and gonorrhea, and as a corrective addition to irritant cathartic pills. It has no advantages over belladonna and is much weaker.

Hyoscyamine (levo-hyoscyamine) is similar in action to atropine, which is a mixture of levo- and dextro-hyoscyamine. Cushny finds that though it acts upon the central nervous system with the same intensity as atropine, it is nearly twice as powerful in its effects upon nerve-endings, especially those of the chorda tympani, of the third nerve in the eye, and of the vagus. It is not readily obtained pure, and is little employed in medicine. Dose of its salts, 1/150 grain (0.0004 gm.).

Hyoscine or scopolamine acts peripherally like atropine, and therefore will allay pain, will dilate the pupil, and will check secretion. But its action in the eye is more rapid and more powerful, a 1: 500 solution dilating the pupil in ten to thirty minutes, and quickly thereafter paralyzing accommodation, while the effect passes fully away in three to five days. Centrally it differs from atropine in that the period of cerebral stimulation is short and is followed by prolonged mild depression of the psychic and motor centers - that is, the drug is narcotic. It has a peculiar amnesic action, at times completely abolishing the memory of events that occurred during its action. In excitable states, as in delirium or mania, it seems to have great power to lessen restlessness or excessive motor activity. Its use is not without danger, however, for it shows early depression of the respiratory and vasoconstrictor centers, and in a great number of instances has caused collapse. Eshner and O'Hara report cases of collapse after 1/100 grain (0.0006 gm.) of the hydrobromide. The writer has seen fatal collapse from 1/50 grain (0.0012 gm.) in an alcoholic man with pneumonia; and collapse with recovery from 1/25 grain (0.0025 gm.) in an alcoholic woman verging on delirium tremens. In both of these the hyoscine had been preceded by 1/4 grain (0.015 gm.) of morphine sulphate. Tileston (1913) says that hyoscine is prone to be followed by Babinski's and Oppenheimer's signs and ankle clonus; in other words, it tends to paralyze segments of the motor tracts. Purves Stewart describes a hyoscine chorea with symptoms similar to those of ordinary chorea. Gregory reports marked delirifacient effects in many cases. Collapse is reported from the use of the drug in the eye.