Nitroglycerin - And How To Use It
( Originally Published 1921 )
BECAUSE the art of medicine pertains to life, comfort, and happiness, it is naturally supposed to be different from other arts and sciences. It was recognized even by the ancients as a difficult art, demanding the highest intelligence and particularly requiring much experience. Yet the treatment of sick human beings is an art which almost every one feels himself competent in a measure to practise, and men who would not think of putting a brush to a picture, a chisel to a statue, or even turning a screw on a machine, will advise people as to the most obscure and elusive ailments, and not only advise them but urge them to undertake some particular form of treatment. Another curious thing about the art of medicine is that people believe that when a piece of work is to be done the only necessity is to select the proper tool to do the work, and that when the tool is once selected almost any one knows how to use it. Selecting the tool in medicine is naming the remedy.
So we hear the expression, "digitalis is good for heart disease," or "nitroglycerin is bad for the heart." Neither of these statements is in-variably true, because everything depends upon how the remedies are used. Nitroglycerin is undoubtedly bad for the heart when improperly used. I have seen many examples of hearts that were badly disordered by Nitroglycerin Nevertheless it is the best remedy in many situations, and when properly used practically the safest remedy there is.
There are some things that every one should know about the use of nitroglycerin, because it is the great emergency remedy. It has the wonderful property of relieving the heart from part of its work and doing this almost instantly. It relieves the heart much in the same way as a man struggling up a steep stairway with heavy bundles would be relieved if some one took some of the bundles from him. It causes the passages through which the blood must be pumped by the heart to be instantly enlarged, so that the blood passes easily and freely, where before it was obstructed. It also has the power of relieving spasms in the circulation wherever they exist, and it can probably relieve a cramp in the heart muscle if such a thing should occur.
Nitroglycerin does all these things instantly and without danger. If it is continued in large quantities and over too long a period of time, it irritates the heart and debilitates the heart muscle, so that it does not contract fully, and it makes the blood vessels unsteady.
Nitroglycerin is therefore a symptomatic remedy, that is, a remedy which is used at a particular time for a particular purpose. Nearly all heart patients are safer if they carry nitroglycerin to use in case they should have any serious disarrangement of the circulation, whether it be pain or shortness of breath or fainting, or indeed anything except perhaps palpitation, and even in- that case it would do no harm.
It is hard to tell in advance how much nitro-glycerin any particular person would need to relieve him. So the safest way is to begin with a small dose, like the 225th of a grain, and re-peat it frequently until the person is relieved, or until some discomfort results. This discomfort consists of a fulness and throbbing in the head and flushing of the face.
Another thing that people should know about nitroglycerin is that often when it is swallowed it is often lost and does not produce any effect. The dose which is advisable is so small that, if it reaches the stomach when the latter is full, a long time is required for it to get into the system; even then the effect may be small because the dose is so diluted.
Nitroglycerin in any form is promptly absorbed in the mouth, so that it is not necessary to swallow it at all; indeed, it is better not to do so. A small granule crushed between the teeth and allowed to rest on the tongue, or a soft tablet put under the tongue in a healthy person will in a few minutes produce throbbing in the head and prove that the drug has been absorbed.
Another thing that people should know is that nitroglycerin, as purchased in the shops, has often lost its strength. It is easy to test it by giving it to some healthy person and noting whether it makes his face flush in a few minutes. It may cause a brief headache, but will not do any real harm.