Part 8

Calomel (Hydrargyri Chloridi Mite).—This preparation is employed internally as a cathartic and gastric sedative, and externally as a stimulating and antiseptic dusting-powder. As a cathartic its best effect is secured by giving it in doses of from ⅒ to ⅙ grain (0.006-0.01 gm.) every half-hour or hour, until a grain has been taken. In this way the whole amount ingested is absorbed. When large doses are employed much of the drug escapes absorption.

Blue Mass or Blue Pill (Massa Hydrargyri).—This is a mixture of mercury, glycerin, honey, and licorice. Its action is much like that of calomel.

Corrosive Sublimate or Bichlorid of Mercury (Hydrargyri Chloridum Corrosivum).—Although irritant, toxic, and destructive to instruments, no other drug has supplanted this salt as an antiseptic for use in general surgery. The following are the strengths of the solutions usually employed for various purposes: for the skin, 1 : 1000 to 1 : 500; for wounds, 1 : 10,000 to 1 : 2000; for cavities of the body, 1 : 20,000 to 1 : 5000. Corrosive sublimate is not a good disinfectant for stools, sputa, etc., as it forms an impenetrable coagulum on the outside of the mass. Internally, corrosive sublimate is used as an alterative in constitutional diseases in doses of ¹/₆₀ to ¹/₁₂ of a grain (0.001-0.005 gm.).

Oxid of Mercury.—This appears in two forms—yellow oxid and red oxid. Both preparations are employed externally in the form of ointments for their alterative properties.

Iodid of Mercury.—This salt occurs in two forms: Red Iodid or Biniodid (Hydrargyri Iodidum Rubrum) and Yellow or Green Iodid (Hydrargyri Iodidum Flavum). The first is an irritating preparation, somewhat resembling corrosive sublimate in its action; the latter is comparatively unirritating, and is much used internally as an alterative. The dose of the red iodid is from ¹/₆₀ to ¹/₁₂ grain (0.001-0.005 gm.); of the yellow or green iodid, ¹/₁₀ to ½ grain (0.006-0.03 gm.).

Nitrate of Mercury.—This preparation is used in the form of a solution (Liquor Hydrargyri Nitratis) as a powerful caustic.

Ointment of Mercury, or Blue Ointment (Unguentum Hydrargyri).—This is an ointment of metallic mercury. It is used as a stimulant and absorbent application in chronic inflammatory swellings, as a parasiticide in certain skin diseases, and by inunction in syphilis. When used for the latter purpose about a dram (4 gm.) should be rubbed in the axilla, groin, or inner surface of the arm or thigh daily, a different region being selected each time, so as to avoid irritation of the skin.

Mercurial Poisoning.—Patients taking mercury continuously, even in small doses, should be carefully watched, as symptoms of ptyalism or salivation sometimes arise very speedily. This condition is manifested by fetor of the breath, soreness of the teeth when the jaws are brought together, increased flow of saliva, redness and swelling of the gums, and finally by ulceration of the tissues, loss of the teeth, and necrosis of the jaw bones. On the slightest evidence of these symptoms the drug should be suspended, and the mouth washed out frequently with a solution of hydrogen peroxid (1 : 4) or of potassium chlorate (1 dram to 8 ounces of water).

The ingestion of a single large dose of an irritant salt of mercury, such as the bichlorid or biniodid, gives rise to severe burning pain in the abdomen, vomiting, bloody purging, and collapse.

=Nitroglycerin.=—This drug is a depressant to the central nervous system, a heart stimulant, and a dilator of the peripheral blood-vessels. It is useful in certain local spasms (asthma), in heart failure, and in neuralgia of the heart. Owing to its action in dilating the vessels, it sometimes causes, even in small doses, headache, dizziness, and flushing of the face.

The dose of nitroglycerin is from ¹/₂₀₀ to ¹/₅₀ of a grain (0.0003-0.0013 gm.). The dose of the 1 per cent. alcoholic solution (Spiritus Glonoini) is from 1 to 5 minims (0.06-0.3 c.c.). The latter should be kept in well-stoppered bottles, in a cool place, remote from lights or fire.

=Nux Vomica.=—This is the seed of an East Indian tree. Its activity depends upon an alkaloid strychnin. It is a general stimulant, acting especially upon the spinal cord, respiratory center, heart, stomach, and intestine. It is employed in a great variety of affections in which there is deficient functional activity.

The limit of tolerance is indicated by restlessness, stiffness of the neck muscles, and jerking of the limbs. Toxic doses cause violent spasms closely resembling those of lock-jaw or tetanus. The convulsions of strychnin-poisoning, however, come and go, the muscles being completely relaxed in the intervals, and, moreover, they rarely involve the muscles of the jaw.

The dose of the Tincture of Nux Vomica (Tinctura Nucis Vomicæ) is from 5 to 20 minims (0.3-1.2 c.c.); of the Extract of Nux Vomica (Extractum Nucis Vomicæ), ⅙ to ¼ grain (0.01-0.016 gm.); of Strychnin Sulphate (Strychninæ Sulphas), ¹/₆₀ to ¹/₂₀ of a grain (0.001-0.003 gm.).

=Opium.=—This is the dried juice of a species of poppy growing in Asia. It contains several alkaloids, the chief of which are morphin and codein. From morphin are prepared artificially two alkaloids—apomorphin and heroin.

Opium depresses the brain, depresses the respiration, stimulates the heart slightly, lessens the peristaltic movements of the bowel, and diminishes all secretions, except the sweat. It is employed to induce sleep, to relieve pain, to allay cough, to check diarrhea, and to promote perspiration.

Opium-poisoning is marked by three stages: the first stage is short and characterized by mental exhilaration; in the second stage the pupils are greatly contracted (pin-point), the respirations are slow, the pulse is slow and full, and there is deep stupor. In the third stage the patient can no longer be aroused (coma), the respiration becomes shallow and irregular, the pulse becomes rapid and weak, the pupils finally dilate, and the patient dies from failure of the respiration.

Even after small doses of opium many patients suffer from headache and nausea. Children are much more sensitive to its action than adults. Morphin resembles opium in action, but is more powerful, less nauseating, and less constipating. Codein is less powerful as a hypnotic and less depressing than morphin.

The dose of opium is from ½ to 1 grain (0.03-0.65 gm.); of the Extract of Opium (Extractum Opii), ⅛ to ½ grain (0.008-0.03 gm.); of the Tincture of Opium or Laudanum (Tinctura Opii), 10 to 20 minims (0.6-1.2 c.c.); of the Camphorated Tincture of Opium or Paregoric (Tinctura Opii Camphorata), ½ to 4 drams (2-15 c.c.); of Dover’s Powder (Pulvis Ipecacuanhæ et opii), 5 to 10 grains (0.3-0.6 gm.); of morphin and its salts (sulphate, hydrochlorate, etc.), ⅛ to ½ grain (0.008-0.03 gm.), and of codein, ½ to 1 grain (0.03-0.06 gm.).

Heroin is chiefly used to allay cough. The dose is from ¹/₁₂ to ⅛ of a grain (0.005-0.008 gm.).

Apomorphin is employed as an emetic and as an expectorant in bronchitis. The dose as an emetic is from ⅒ to ⅙ of a grain (0.006-0.01 gm.), always hypodermically; the dose as an expectorant is from ¹/₂₀ to ¹/₁₀of a grain (0.003-0.006 gm.), always by the mouth.

=Paraldehyd.=—This is an oily liquid, having a peculiar unpleasant odor and taste. It is used chiefly as a hypnotic. While comparatively safe and reliable, its disagreeable taste and persistent odor on the breath detract from its usefulness. The dose is from ½ to 1 dram (2-4 c.c.), in some pleasant vehicle.

=Phenacetin.=—This anilin derivative has properties very similar to those of acetanilid, and is used for the same purposes. Dose, 5 to 10 grains (0.3-0.6 gm.).

=Physostigma.=—This is the seed of a climbing plant growing in Africa. Its activities depend upon an alkaloid known as eserin or physostigmin. It depresses the spinal cord, stimulates the peristaltic movements of the bowel, and, when applied to the eye, contracts the pupil. It is employed to check certain convulsions (tetanus and strychnin-poisoning), to overcome atonic constipation, and, locally, to contract the pupils.

The dose of the Tincture of Physostigma (Tinctura Physostigmatis) is from 5 to 20 minims (0.3-1.2 c.c.); of the Extract of Physostigmatis (Extractum Physostigmatis), ¹/₁₂ to ⅙ of a grain (0.005-0.01 gm.); of eserin or physostigmin and its salts, ¹/₁₅₀ to ¹/₅₀ of a grain (0.0004-0.0013 gm.).

=Pilocarpus=, or =Jaborandi=.—This is the leaves of a South American plant. Its virtues depend entirely upon an alkaloid known as pilocarpin. The chief action of the drug is on the secretions—sweat, saliva, and urine—which it markedly increases. Large doses depress the circulation. Locally, in the eye, it contracts the pupil like eserin. It is mainly employed internally as a diaphoretic in Bright’s disease and dropsical conditions. The dose of the Fluid Extract (Extractum Pilocarpi Fluidum) is from 20 to 60 minims (1.5-4 c.c.); of pilocarpin and its salts, ⅛ to ½ grain (0.008-0.03 gm.). The latter are usually administered hypodermically.

=Quinin.=—See Cinchona.

=Salicylates.=—These salts are employed in medicine chiefly as antirheumatic remedies. Their manner of action, however, is unknown. They are also used, both internally and externally, to some extent as antiseptics. Large doses cause ringing in the ears, headache, deafness, nausea, and a greenish discoloration of the urine.