(From vol. iv. 2nd edit., 1825.)
[The alcoholic solution of the almost crystalline substance resembling a solified aetheral oil, derived from the camphor-tree, Laurus camphora, L.]
I give here the symptoms hitherto observed from camphor, not as a complete list of all the effects to be expected from it, but only as a commencement thereof, so that at some future period the remainder of its effect may be added to this list.
From the earliest times this medicine has been blindly used and improperly employed in large and massive doses, so that its true action has never been ascertained, nor could it be acertained, as it has almost always been given only with several other drugs, either mixed up with, or administered at the same time with it, and moreover, and this is the worst, it has only been employed amid the tumult of the symptoms or diseases. For the pure effects of it, observed by ALEXANDER, (WILL, ALEXANDER, Medical Essays and Observations, 1755.), are very meagre and confined to mere general expressions.
The action of this substance is very puzzling and difficult to determine, even in healthy organisms, because, its primary action more often rapidlyalternates and becomes mixed up with the reactions of the life (secondary action) than is the case with any other medicine, so that it is frequently hard to distinguish what is to be ascribed to the reaction of the body, and what to the alternating action of the camphor in its primary action.
But, at all events, commencement of a pure proving of it must be made, and as such I offer the following symptoms.
In its curative action camphor is just as puzzling and wonderful, for it removes the violent effects of very many, extremely different, vegetable medicines (and even those of the animal drug cantharides and of many mineral and metallic drugs), and hence it must have a sort of general pathological action, which, however, we are unable to indicate by any general expression; nor can we even attempt to do so far fear of straying into the domain of shadows, where knowledge and observation cease, we, in short, abandoned by the guiding of plain experience, grope about in the dark, and with every desire to penetrate into the inner essence of things, about which little minds so presumtuously dogmatize, we gain nothing by such hyperphysical speculations but noxious error and self-deception.
Camphor, as I can testify from experience, removes the too violent action of very many drugs, whether unsuitably employed or given in too large doses, but generally only in the primary action, as a kind of contrarium, as a palliative. For this purpose it must be given very frequently, but in very small doses – when requisite every five to fifteen, or when there is great urgency every two or three minutes, about one drop of the saturated alcoholic solution (one eighth of a grain) shaken up in half an ounce of water until dissolved, or by means of olfaction of a saturated alcoholic solution of camphor every three, four, six, ten, fifteen minutes.
One grain of camphor (dissolved in 8 drops of alcohol) combines with 400 grains of tepid water, and when shaken becomes completely dissolved, contrary to the assertion in almost all works on materia medica that is quite insoluble in water.
I have not found camphor suitable as an antidote to the violent effects of ignatia. (In the preface to Ignatia, camphor is said to be the antidote to some of its effects.)
The rapid exhaustion of its action and the quick change of its symptoms render it incapable of curing most chronic diseases.
That cutaneous inflammation, which spreads in a radiating manner, is bright red, the redness disappearing for an instant when pressed with the finger, commonly called erysipelas (rose), when it arises from internal causes is always only a single symptom of the disease. Now, as camphor when applied externally excites a kind od erysipelas, so, in acute diseases accompanied by erysipelas, it is useful as an external application, if the other symptoms of the internal malady are present among the symptoms of camphor.