Narcotics may be defined to be agents which lessen the sensibility and irritability of the nervous system. They first act as excitants to the nervous and vascular systems, and secondarily, as sedatives to the sensorial and vital powers; and if given in suitable doses, they produce torpidity of all the functions, insensibility and sleep. The encephalon, and its appendages, it would seem, are the parts upon which the influence of narcotics are principally expended.
Narcotic and sedative are generally considered as synonymous terms, and the general opinion is, that a narcotic agent is sedative, and vice versa. It is true, that most of the narcotics are sedative—their secondary influence being that of sedation. On the contrary, many articles having no narcotic property, and rarely if ever used as such, are commonly classed with narcotics, as digitalis, veratrum viride, lycopus, etc.; and again many therapeutic agents, used as sedatives, are never classed with narcotics, as nauseants, kalmia latifolia, prussic acid, prunus virginiana, the lancet, tartrate of antimony, etc. From these considerations it will appear that, at present, no well-marked line of separation between the two classes of agents commonly denominated narcotic and sedative, exists; and yet we think there is sufficient difference in their therapeutic action and applicability, to warrant a distinction, notwithstanding the same articles, many of them, may possess properties, and fulfill indications common to both. As has already been intimated, the principal difference between the two classes, consists in the primary excitation consequent on the administration of narcotics—the secondary effects in both cases are quite similar. Sedatives, however, do not possess the anodyne, or soporific properties which characterize narcotics, and consequently are adapted to the fulfillment of somewhat different indications in the treatment of disease. The latter are administered as anodynes and hypnotics; they alleviate pain, allay nervous irritation, counteract spasm and procure rest; while true sedatives are administered to subdue preternatural excitement, to abate excessive or exhausting organic movements, and to counteract excessive vascular action.
Action of Narcotics.—All narcotic agents are soluble in the fluids of the body, and hence they are readily absorbed; some of them are very soluble, and their absorption is immediate; hence they act very rapidly. The remedy after being absorbed is conveyed by the circulation to the nervous centers, and produces its specific effect upon them. Why a certain agent will act as a narcotic, and what effect it has upon the nervous system is not known, and probably never will be; we therefore have to be satisfied with a knowledge of the symptoms it produces. That this class of agents are absorbed, and are carried by the blood to the part on which they tend to act, has been proved beyond a doubt. Thus those agents will produce their specific effects when absorbed from any part of the system, or when injected under the skin. Another evidence that they are absorbed into, and act from the circulation, is the celerity with which they produce their narcotic effects when applied locally. Opium, for instance, when applied to ulcers produces costiveness, headache, nausea, etc., and in short, the endermic or topical application of it is followed with the same unpleasant symptoms that attend its internal exhibition.
The attempts to ascertain the locality upon which these agents act, has not thus far been attended with much success. Flourens was of the opinion that opium acted specifically upon the cerebral lobes; that belladonna, when the dose was small, acted upon the tubercula quadrigemina, and in large doses upon the cerebral lobes also, etc. These opinions were founded entirely upon the symptoms produced by the agent, and not by any pathological change in the part supposed to be acted upon.
Narcotics also act directly upon the nerves of the part with which they are brought in contact. Thus when taken internally they prove topically sedative to the nerves of the stomach, and are often thus used to relieve the pain in gastrodynia, to allay the excitement and irritation of the gastric nerves in nausea and vomiting, etc. When taken before eating they often lessen the appetite, and may even destroy it by lessening the gastric innervation; for the same reason they retard the process of digestion—chymification, chylification and defecation may be arrested by the paralyzing influence of the narcotic.
The first sensible influence of narcotics upon the system, when administered in either excitant or sedative doses, is an increase in the activity of the circulation and cerebral functions:—the force and rapidity of the pulse is augmented, the skin becomes hotter and drier, and there is increased mental and physical activity. They produce vivacity, a lively imagination, quicken the perceptive faculties, and give muscular vigor and courage. If, however, the agent is administered in doses sufficiently large, the excitement will be of short duration, and the anodyne and soporific effect will be more intense and continue longer. The relative intensity of these primary and secondary effects varies in the different narcotics, and even in the same narcotic in different doses. If the dose is large, heaviness of the head, dullness of the intellectual faculties, dimness of sight, muscular weakness, diminution of the motor power, prostration and loss of energy, and a tendency to coma are the results. In some cases vertigo, cephalalgia, convulsions, hallucinations, total loss of the mental faculties,—and if the dose of the narcotic is sufficiently powerful,—a profound coma ensues; the pulse is full, slow and laboring; the respiration slow and stertorous; in a few hours the skin becomes cool and clammy, and the extremities cold; the pulse is feeble and threadlike, and death follows. Death is supposed to result from deficient innervation of the respiratory organs; the narcotic overpowers the brain and nervous system, due innervation is not transmitted to the respiratory apparatus, there is not sufficient aeration of the blood, and the patient dies asphyxiated.
Notwithstanding the deadly effects which they occasionally produce, when injudiciously taken, they can be used in suitable quantities to secure their anodyne and hypnotic influence with as much safety and certainty of success, as emetics or cathartics, in the various cases in which they are prescribed.
The modus operandi of each narcotic seems to be peculiar to itself; each seems to exert an influence over the sensibilities of the system, in some particulars different from any other. Thus, after one has failed to induce sleep, complete success will often attend the administration of another; and here lies the great advantage of having recourse to a variety of different agents whose general properties are the same.
By the sedative influence of narcotics upon the nervous system, their general tendency is to lessen the secretions of the different organs, as the liver, kidneys, mucous secretions, etc., when the parts are in a normal state; hence they produce constipation, by lessening the secretions poured into the bowels, and by deadening their sensibility and lessening their peristaltic action. It is true there are exceptions to this general rule, for some of the agents of this class promote instead of retarding the secretions; while others which lessen them in a healthy or normal state of the organs, often restore them when diminished or arrested. In opposite pathological states of the same organ, when the secretion is either diminished or excessive, they often restrain it when too profuse, and promote it when scanty, and thus exert a marked control over the secretions. When speaking of opium we shall endeavor to illustrate this peculiar action, and the proper therapeutic application of this class of agents to such cases.
The three principal indications which the physician wishes to accomplish by the administration of narcotics, are the alleviation of pain, the production of sleep, and the relief of spasm. As antispasmodics their utility is dependent upon their anodyne properties. There is one circumstance connected with the administration of narcotics as anodynes or hypnotics which deserves a passing notice. The physician is often disappointed when he prescribes them as soporifics, when most desirous of securing repose to his exhausted and tortured patient. The disappointment springs from administering the agent in excitant, and not in sedative doses. If administered in doses not large enough to secure sleep, it augments the excitement, and maintains wakefulness, and often begets a morbid vigilance. If the dose is increaeed, the nervous and vascular excitement, the excessive organic action and pain are alleviated, and all care and anxiety subside; the morbid sympathies are arrested, the mental and physical turmoil ceases, and the patient falls into a calm and comfortable state of repose, to awake invigorated and refreshed.
Those who clamor so vehemently against the use of narcotics, and offer as substitutes "relaxants, nervines and antispasmodics," deprive themselves of an invaluable class of medicines without pointing out, or being able to point out real substitutes; they have no medicines with which they can produce the same happy and very desirable influences.
If the disease in which narcotics are administered is of a protracted character, and the frequent and long-continued use of them becomes necessary, the dose will require to be augmented. The system gradually, and with more certainty loses its susceptibility to this class of agents than any other; and hence the necessity of duly increasing the dose.
With regard to their therapeutic application to particular diseases, much might be said, but we will omit many points until we come to the description of particular agents of this class. They are adapted to certain stages of almost all diseases; sometimes they are prescribed as independent curative agents, but more frequently as auxiliaries, and not unfrequently, simply as palliatives.
I. Action in Diseases of the Lungs.—Opposite opinions obtain relative to the use of narcotics, and particularly with regard to the use of opium (which, in some respects, is sui generis), in the various forms of pulmonic inflammation, because it is said to arrest the mucous secretions; but it would seem that the objection to the use of this article, either in the primary or secondary forms of this class of diseases, is not founded upon a proper understanding of the pathological changes which follow from its use, or which take place spontaneously as the disease advances. During the early stages of pneumonia and bronchitis, the acute inflammatory action either arrests or greatly diminishes the normal secretions; the suppression being due to the pathological condition of the mucous membrane. In such cases small doses of opium would increase the intensity of the inflammation as readily as any other excitant; and if the secretion was not arrested, but only diminished, it would entirely arrest it by its excitant influence upon the system. Now, if given in sedative doses, it will change the pathological condition which caused the arrest of the secretion; nauseating expectorants combined with it would render it doubly valuable. In sedative doses its influences would be reversed; it would lessen the intense inflammatory action which caused the diminution or arrest of the secretion, and thereby contribute to its restoration.
In the advanced stages of the acute form of the above diseases, or in their chronic form, the pathological condition of the inflamed parts has materially changed since the acute inflammation existed; which change is characterized by an increased or profuse morbid secretion from the mucous membrane. In this case it will diminish the secretion, by diminishing the inflammation upon which the increased secretion is dependent; thus they may be said to promote it in the first case, and diminish it in the second.
In the last stages of phthisis pulmonalis, in many cases, the administration of narcotics is an act of mercy, smoothing the sufferer's pathway to the grave. They lessen the irritability of the lungs, check the harrassing cough, relieve the pain, check colliquative diarrhea, and in this way not only prolong life, but make the last days of the patient, if not easy, endurable.
II. Action in Diseases of the Stomach and Bowels.—In gastrodynia narcotics are valuable for their topical influence upon the nerves of the stomach; they often produce a local torpor of these nerves, and thus relieve the severe pain. In irritability of the stomach producing continued nausea and vomiting small portions of morphia will allay this irritation, and check nausea and vomiting without producing anv sensible effect upon the general system. The same agent is often employed in very minute doses in combination with demulcents in acute gastritis, and with marked success.
In peritoneal enteritis there is a concentration of morbid sensibility and irritability, connected with excited organic action in the peritoneal and muscular coats of the bowels; the tension of the parts, owing to the active inflammation, approaches a spasm. This concentration of vital organic action in the exterior coat of the bowels, acts as a derivative to the mucous membrane, and thus its secretion is diminished, and the combined influences often produce obstinate constipation. Opium, by its contra-stimulant power, lessens the inflammatory action and morbid sensibility, restores the secretions, removes the spasm, and may act indirectly as an aperient, and even aid the action of cathartics.
The same narcotic is administered in another form of inflammation, both to restore and restrain the secretions and excretions. In diarrhea, we have an inflammation of the mucous coat of the intestines, with augmented secretion soon after the attack, and with frequent alvine evacuations, owing to increased peristaltic action. Opium lessens the undue activity of the bowels, and their morbid sensibility; it tends to arrest the inflammation by its contra-stimulant powers, changes the pathological character of the disease, and diminishes the secretions; and thus acts indirectly as an astringent.
The same article in the two cases just referred to, exerts the same influence in each, yet owing to the opposite pathological conditions existing in the two cases, the results vary. In the first instance the secretion is increased, and a laxative influence produced; in the second, the secretion is diminished, and constipation follows.
For the same reason that opium is so valuable in peritoneal enteritis, it is also valuable in that painful affection, colica pictonum, and in nervous and spasmodic colic. In these cases there is a diminution of the secretions, a violent tension, or even spasm of the muscular coat, obstinate constipation, etc., attended with violent pain. In such a case, a sedative dose of opium allays the pain, resolves the spasm, promotes the secretions, and facilitates the action of cathartics.
III. Action in Fevers.—In febrile and inflammatory diseases they are valuable as anodynes, as sedatives, and as diaphoretics. As anodynes they are very beneficial in relieving pain and subduing nervous irritability, which very frequently greatly aggravate the disease. As sedatives or hypnotics, they induce sleep, and thus directly sustain the strength, by calming the existing excitement, and allowing that repose which nature demands; they also prevent, according to some authors, the rapid oxydation which is taking place in these diseases. By subduing exalted organic action, overcoming the tension of the muscular system, and removing cutaneous spasm, they prove highly antiphlogistic, and valuable auxiliaries to nauseants, diaphoretics and refrigerants.
IV. Action in Local Diseases.—A local injury or a morbid exaltation of organic action of a local character, from whatever cause it may arise, very often produces general disease, and not unfrequently destroys the patient, from the severe pain and nervous irritability which it induces. Thus a burn, bruise, or abrasion of parts, a painful tumor, boils, felons, irritable ulcers, white swellings, gout, rheumatism, etc., by their high grade of local excitement, may involve the whole eyetem in a general diseased state, through the sympathetic irritation which it produces in all parts of the system. From a wound or an injury done to a nerve, as by the thrust of a nail, thorn, or any sharp instrument, at any season of the year, but especially during the hot season, when there is increased irritability and excitability of the nervous system, that formidable disease, tetanus, not unfrequently results. In such cases a sedative dose of a suitable narcotic, together with the topical application of a similar agent, lessens the impressibility of the nervous system in general, and the nerves involved in particular, and prevents the cerebro-spinal centers from appreciating the local injury, until suitable means can be adopted to allay the local irritation, and prevent the morbid effects upon the entire system.
In numerous cases of both local and general disease, the induction of sleep by the use of narcotics, which at the same time are capable of allaying pain and excessive vascular and nervous excitement, so prejudicial to recovery, and even destructive to the life of the patient, if permitted to continue long unabated, is of the utmost importance. In cases of violent neuralgic pain, arising from loss of blood, and not dependent upon vascular repletion or cerebral inflammation, a sedative dose of opium will speedily alleviate the pain, and subdue the vascular excitement.
In cancerous, scrofulous and syphilitic diseases, where there is much irritation, pain and general excitement, they will prove valuable palliatives, and may, as auxiliary agents, exert a salutary curative influence. In incurable cancer, where the pain is severe, and the repose of the sufferer thereby interrupted, they afford great relief by allowing repose, and invigorate the system by securing a temporary respite from the protracted torture.
Narcotics are very important as topical agents, in painful scirrhus, or scrofulous tumors, hernia humoralis, nodes, buboes, or in any local or painful inflammatory affection. The sedative and anodyne influence of narcotics in the form of poultices, liniments, ointments, etc., renders them valuable therapeutic agents. They lessen the pain by their sedative, anodyne and emollient influence, and prove exceedingly valuable as discutients, if the suppurative process is not too far advanced. If there is no chance for discussion, they will advance suppuration.
In cases of cancer of the uterus, bladder or rectum, in cases of hemorrhoids, or any painful and irritated condition of those parts, narcotics are occasionally used with much advantage as palliatives, and not unfrequeutly prove beneficial as curative agents. They may be used in the form of injections, ointments, etc.
They are of great importance in the various spasmodic diseases. As anodynes they calm and allay that morbid erythism of the nervous system, and the inordinate organic action upon which spasm depends.
Their value is very considerable in neuropathic diseases; in all the numerous forms of which, as mania, hysteria, delirium tremens, etc., narcotics occasionally procure more or less relief.
In many cases of troublesome cough, occurring during the cold and variable season of the year, and arising from an irritation of the pneumogastric nerves, distributed to the mucous membrane of the air-passages, and not dependent upon an inflammation, narcotics, particularly opium, or morphine and its salts, will allay the irritation, and check the tickling cough, generally very promptly.
Conditions Contraindicating their Use.
Narcotics are contraindicated in cases of extreme debility unless they are of a stimulant character, and administered in stimulant doses, or in combination with stimulants. They are also objectionable in encephalitis, and in paralysis, unless it is connected with, or dependent upon some local irritation or inflammation; when if other symptoms seem to demand their employment, they may be used.
Notwithstanding the numerous cases in which they are used, and the immense advantage gained by their employment, yet it must be confessed that their long-continued use is prejudicial to the well-being of the patient; for their general tendency is to destroy the functions of the nervous system. The same remarks, however, will apply with much force to the constant and continued use of medicinal agents generally. A dry skin, dry tongue, and hard pulse, contraindicate the majority of narcotic remedies. They are administered, when needed, when the skin is soft and moist, the pulse soft, and the tongue moist.
1st. They are administered as anodynes in cases of inordinate and excessive pain.
2d. They are prescribed in various acute diseases, attended with morbid vigilance, as hypnotics—or with a view to the production of sleep.
3d. They are useful as antispasmodics; in spasm of any part they are used with advantage, from the fact that they diminish innervation, as well of the motor as of the sensitive nerves.
4th. They are administered as sedatives in febrile and inflammatory diseases, to allay exalted organic action, as well as to alleviate pain; they are also administered, to secure their diaphoretic influence, either alone or in combination with other agents; also as stimulants, when given in small doses, in the advanced stages of fever.
5th. In cases of acute pneumonia they are administered in sedative doses, to restore the pulmonary secretion.
6th. During the secondary stage of pulmonic inflammation, when the secretions are profuse, they are administered to check them.
7th. In acute inflammation of the mucous membrane of the bowels, they arrest the secretion, lessen the pain and increased peristaltic action, upon which the frequent purging depends.
8th. In cases of colica pictonum, or peritoneal enteritis, they allay the pain, resolve the spasm, and facilitate the action of cathartics.
9th. In injury of a nerve, or excessive local pain, they prevent the brain from appreciating the local lesion and pain, until suitable local applications can be made, and the morbid sensibilities lessened; and thus prevent general disease, and often save the life of the patient.
10th. In irritation of the pneumogastric nerve, attended with a severe cough, in irritation of the mucous membrane of the stomach attended with nausea and vomiting, they often give prompt and speedy relief.
11th. In the varions forms of neurosis, they are used as sedatives, anodynes, and antispasmodics.
12th. In cases of incurable cancer, and other incurable diseases, they are resorted to as palliatives, relieving the pain, procuring sleep, and making the last days of the patient more comfortable.
13th. As topical applications in scirrhus, scrofulous and all painful tumors, painful and irritable ulcers, hemorrhoids, cancer of the uterus, etc., they are important as local anodynes, discutients and emollients.
The American Eclectic Materia Medica and Therapeutics, 1898, was written by John M. Scudder, M.D.