Dry coughing, when persistent, is greatly a matter of habit acquired by yielding to slight irritation. When children scratch their heads we train them [{346}] not to, and the same thing should be done with regard to yielding to reactions from slight irritations of their lungs.
Even when material has to be expectorated there is often much more fuss and effort made over it than is needed. Most men a generation ago insisted on their right to expectorate in public because it was better for them to rid themselves of offensive material than to retain it. The difference between men and women in this respect has always been distinctive. Women practically never expectorate in public, men do it frequently, or rather, let us hopefully say, used to. It seems to be thought the exercise of a manly privilege to spit and the boy learns the habit. It seemed almost a necessity in the past, yet now we have come to a point where, by legal regulation, we prohibit spitting in public and it seems likely future generations, not far off, will hold it as a rule that instead of the sexes being essentially different by nature in this respect, the habits formed by the enforcement of recent legal regulations will show their essential similarity and we shall have no "expectorating sex."
Unnecessary Coughing Harmful.—Coughing, unless it is necessary, always does harm. It irritates the mucous membrane, already rendered somewhat hyperemic and tender by the inflammatory process at work, to have the breath pass over it in such an expulsive way. This is one case where nature's indications are not to be followed. It is like itchiness in eczema: it needs to be restrained. The cold will get better sooner, the inflammatory process will run its course with less disturbance and in briefer time than if it was not disturbed in this way or disturbed only as little as possible. This is a point that is not often explained to patients and most sufferers from colds are inclined to think that the more they cough the better, even though the cough, like the scratching in eczema, evidently produces a roughening and sensitizing of inflamed tissue. Of course, this principle of the limitation of cough may be carried to excess and indeed sometimes is when opium is administered to quell coughing. This is not the idea, however, of the suggestion made here, which is only to restrain the cough within the limits necessary for the removal of material that should be evacuated.
The history of most of the tuberculous patients who suffer from hemorrhage for the first time shows that they had been coughing unproductively, and then, after coughing in this way rather severely, there came the flow of blood due to the rupture of a minute artery. In these cases the tuberculosis process has been at work for some time and has prepared the tissue for this arterial rupture, but there is no doubt, however, that the coughing itself, far from doing good, rather helped in the destruction of lung tissue, or at least made it more difficult for natural processes in the lungs to wall off the bacilli and prevent further damage. Practically every adult is in some danger of lighting up an acute tuberculous process in his lungs if he racks them by coughing. There are many similar examples in nosology of this possibility of some habit predisposing to or favoring the development of disease.
After measles and whooping cough tuberculosis is especially likely to develop. In both of these diseases, but especially in the latter, coughing is an element of the affection that probably predisposes to the implantation of the tubercle bacillus so commonly present in the air of our cities. The lesions produced in the extreme expulsive efforts of the paroxysm form favorable niduses for the micro-organism. Children particularly, if at all encouraged, are likely [{347}] to cough more than is good for them. On the slightest irritation they cough. It is almost impossible to restrain them from scratching when they are suffering from eczema, yet we take rather elaborate means to do so, and quite as much must be done to prevent them from coughing when there is no special reason for it. This does not refer to cases in which material is being abundantly expectorated. Elimination can only be secured by a proper expulsive effort. Very often, however, children notice how much solicitude their little dry cough arouses. They like to be the objects of attention. They are dosed with various cough remedies, more or less pleasant, whenever they cough. Instead of being told that they should restrain their cough except when it is necessary, they are rather encouraged to cough whenever there seems to be the slightest occasion.
Reflex Coughs.—There are a number of coughs that are said to be reflex because they are not induced by any lesion of the lungs or of the larynx, or, indeed, of any of the air passages. In these cases some pathological condition is often found in another organ or set of organs, usually one of those connected with the vagus nerves. The wide distribution of these pharyngo-laryngo-esophago-pulmano-cardio-gastric nerves gives ample opportunity for reflexes. We hear much of reflex cough. There is a stomach cough and an intestinal cough, a uterine cough, an ear cough, etc. These coughs are always dry, though often very irritating to patients, and especially may be a source of dread and disturbance of mind and health because they seem to signify some serious pathological condition. As a rule, these coughs can be restrained to a great degree and frequently suppressed entirely by suggestion and discipline. In many cases there is some temptation to cough consequent upon irritation of nerve endings communicated through some devious paths to the nerve supply of the respiratory tract, but this tendency is not very strong and can be easily overcome. It may be said that this is asking too much of human nature, and that, just as sneezing carries with it a certain satisfaction and so is apparently worth the trouble of indulging in, coughing should be permitted, at least, if not encouraged, but the reasoning is fallacious.
Habit Coughs.—An interesting cough that comes to the physician is that in which there is absolutely no pathological reason to account for it. There is an irritation of the mucous membrane somewhere along the respiratory tract but it is very slight and somehow the habit has been acquired of yielding to the reflex that it occasions. I have seen these coughs in children in cases where I was sure that they were nothing but tics. I have seen so-called hacking coughs in girls of twelve to sixteen that were explained as ovarian, or sometimes as puberty coughs, that were really nothing more than habits. A slight hyperemia of the mucous membrane in the upper respiratory tract due to an ordinary cold began in a very slight degree the irritation, and then the habit of coughing was not given up. Of course, I know the danger of treating such cough as habit coughs. Tuberculosis in its initial stage may exist for a prolonged period before it produces any increase of secretion and at a time when none of the ordinary physical diagnostic signs are present, except possibly a little prolongation of expiration over the affected area. At this stage tuberculosis will sometimes produce gastric disturbance, and, as I have already said, these are spoken of as stomach coughs when there really is something much more serious than them at work. When there has been no running down in [{348}] weight, and, above all, no special opportunity for contagion, then, if there are no physical signs in the lungs, these coughs will be best treated as habits and gradually be made to stop by suggestion. The limitation of coughing will do good in any case.
Coughs as Tics.—Some coughs are not really due to any difficulty in the respiratory tract, but are caused by nervous irritability. There are certain habits in the matter of clearing the throat that sometimes become pronounced and apparently impossible to stop. As I have said, these are tics rather than true coughs. Many of these neurotic coughs very seriously alarm patients and also their friends. They are dry, as a rule, rather harsh and inclined to be brassy. Occasionally they are only what is known as "hacks," as if the patient were trying to clear the throat of some offending material. Of course, at no time must the significance of cough be made light of unless a careful investigation of the patient's condition has been made.
Diagnosis.—Names for these coughs should not be too readily accepted which, by satisfying legitimate curiosity and lessening proper apprehension with regard to them, will stop further investigations. Besides stomach coughs, one often hears of intestinal and even uterine or ovarian coughs. In many cases the real condition is one of an incipient tuberculous condition and there may be no sign of this except a disturbance of the pulse and perhaps a slight variation of the temperature range for the day (two degrees or more Fahrenheit in the twenty-four hours). Such coughs should always be carefully investigated for the possibility of incipient tuberculosis. At once the patient should be warned about coughing without necessity, since this only tends to disseminate the tuberculous process and may help to break down nature's wall of protective lymph.
Where there is no disturbance of pulse or temperature and the patient is not under weight and there are no signs in the lungs, then the cough is merely a habit and partakes of the nature of a tic. Sometimes these habits are rather difficult to break; always, however, much can be done by suggestion, by a habit of self-control, by self-discipline, and by thorough persuasion of the patient. Drugs are likely to inveterate the condition if not allied with suggestion.