Codeina

Codeine. White, or yellowish-white, more or less translucent, rhombic prisms, somewhat efflorescent in warm air, odorless, having a slightly bitter taste and an alkaline reaction. Soluble in eighty parts of water at 60° Fahr. and in seventeen parts of boiling water; very soluble in alcohol and in chloroform; also, soluble in six parts of ether. Dose, gr. ss—gr. ij.

Various salts of codeine are now prepared, but the sulphate is the most important and desirable.

The other alkaloids of opium are not official.

Narcotinae Hydrochloras

Hydrochlorate of narcotine (not official). Dose, gr. ij—gr. x, as an antiperiodic.

Antagonists and Incompatibles

As regards chemical antagonism, the alkaline carbonates, lime-water, and the salts of iron, lead, copper, zinc, mercury, and Fowler's solution, are incompatible with the preparations of opium. Notwithstanding this chemical incompatibility, the metallic salts are frequently given in conjunction with opium, and the systemic effects of both are produced. Astringent vegetables (tannin) are also incompatible; they limit physiological activity by forming tannate of morphine, which is not readily soluble.

In cases of opium-poisoning, if any portion of the drug remain un-absorbed in the stomach, the most prompt and efficient emetic should be used. Apomorphine should be injected subcutaneously, if the patient is unable to swallow; if conscious, the sulphate of copper may be administered by the stomach. In a case of opium narcosis which resisted ordinary emetics, violent emesis was induced by a solution of bicarbonate of sodium, followed by a solution of tartaric acid. In the absence of other and more active emetics, powdered mustard may be administered—a table spoonful to a tea-cupful of warm water. When the opium swallowed is in solution, the stomach-pump should be used if the narcosis is profound. Cold affusion, artificial respiration, when the breathing flags, and faradization of the chest-muscles, are measures of great practical utility. The author has personally witnessed in several cases the excellent effects of faradization, first, in causing such irritation of the surface as to produce reflex excitation of the respiratory center; and, second, inducing contractions of the respiratory muscles. As a peripheral irritant, faradization is more humane and seemly, and also more efficient, than flagellation.

The action of opium is antagonized, at least in a part of the sphere of its influence, by belladonna. These agents are opposed as regards their influence on the intra-cranial circulation, on the pupil, on the respiratory organs, and on the heart. Opium in lethal doses causes paresis of the arterioles and veins; belladonna contracts them, and, by energizing the cardiac movements, substitutes an active for a passive congestion. It can not be too strongly insisted on in this connection that belladonna in too great quantity, or too long in action, exhausts the irritability of the unstriped muscular fiber, and thus induces the very state which its administration was intended to relieve. The state of the pupil, the action of the heart, and the condition of the reflex movements, are the guides to the administration of belladonna in cases of opium narcosis. The smallest quantity of belladonna which will dilate the pupil, raise the tension of the arterial system, deepen the respiration, and re-establish the reflex excitability, should be used. The author has a strong conviction, arising from some painful personal experience, that it is a fatal error to attempt to restore a patient in opium narcosis to complete consciousness by repeated doses of belladonna. The action of these agents combined is to produce profound sopor, and this is not a condition of danger so long as the pulse, respiration, and reflex movements are in good condition. To substitute belladonna narcosis for opium narcosis is only increasing the hazard under which the patient is already struggling. Impatient to afford relief, and assuming that the tendency to sleep must be obviated, the physician too frequently, as the history of many cases plainly shows, repeats the doses of belladonna until its action greatly preponderates, and the irritability of the cardiac ganglia is completely exhausted. The author, therefore, feels himself warranted in repeating that the utility of belladonna consists in its power to maintain the action of the heart, and the respiration, until elimination has taken place, and that even coma is of little importance provided the respiration, circulation, and reflex movements are properly maintained.

The hypodermatic injection of atropine is the most efficient and satisfactory method of employing this physiological antagonist. Not more than 1/120 of a grain of the sulphate should be administered at a dose, and this may be repeated every fifteen minutes (up to three doses) until dilatation of the pupil, increased power of the cardiac movements, deeper respiration, warmth and dryness of the skin, and flushing of the face, are produced. No more can be accomplished by the largest doses, and the results of the antagonism must be awaited. Belladonna continues longer in action than opium. In a succeeding chapter, devoted to the consideration of the combined administration of opium and belladonna, or morphine and atropine, the nature and degree of the antagonism will be more fully elaborated.

Coffee is also an antagonist to opium, especially caffeine subcuta-neously, in doses of three to five grains, repeated as may be required, up to twenty grains. Good results have undoubtedly been obtained by the free use of black coffee, in milder cases of opium narcosis. The unpleasant confusion of mind, and vertigo, which in so many subjects are experienced after the subsidence of the effects of a medicinal dose, may sometimes be removed by a cup of strong coffee. These cerebral effects may be prevented, or relieved when they occur, by a full dose of bromide of potassium. This discovery, if we may dignify so small a matter by so imposing a title, was briefly announced by the author in the first edition of his work on "Hypodermatic Medication."

Gubler has shown that some of the cerebral effects of opium are antagonized by quinine. Tartar emetic and digitalis also oppose to some extent the action of this remedy on the intra-cranial circulation.

Synergists

The cerebral and hypnotic effects of opium are promoted by alcohol and its derivatives (notably chloral), and, within certain limits, by the mydriatics. The sudorific action of opium is increased by ipecacuanha.