These facts may tend, in some measure, to remove any existing fears as to the safety of arsenic, used with due caution as a medicine; but they should not render the practitioner careless. if the dose never be allowed to exceed the legitimate limits, and the medicine be suspended or suitably diminished on the occurrence of any unpleasant symptom, no danger of serious injury from its use need be apprehended; but recklessness or negligence may, in the employment of this, as of any other powerful remedy, lead to irreparable mischief.

Poisonous Effects

Sometimes, when a large quantity of powdered arsenious acid is taken on a full stomach, the poison is wholly rejected along with the gastric contents, and no ill effects follow. A case is related, in which half an ounce was swallowed, with the effect of vomiting, and without causing death. But such cases are very rare. Generally, the poisonous symptoms from arsenious acid make their appearance in about half an hour, or an hour, after it has been swallowed, but occasionally in a very few minutes; and instances are on record in which they have been postponed for several hours, in one case so long as eight. A severe burning pain is felt in the stomach, usually increased by pressure; nausea comes on, quickly followed by vomiting, and somewhat later by diarrhoea; the ejected matters produce inflammation of the mucous surface over which they pass, giving rise to a sense of constriction and burning heat in the throat, with a deep-purplish redness of the lips and mouth, and intense thirst; the vomiting becomes incessant, with the discharge of everything taken into the stomach; the diarrhoea is often attended with tenesmus, and occasionally with excoriations of the anus; the abdomen becomes swollen, hard, and extremely tender; sometimes the skin is hot, sometimes pale and cold, with a clammy sweat; the pulse is frequent, small, irregular, and at length extremely feeble or imperceptible; the respiration is often laboured, from the pain produced by the descent of the diaphragm; palpitations, faintness, great prostration, cramps in the extremities, and hiccough, mark the implication of the nervous system; and, finally, delirium, tetanic spasms, convulsions, and paralysis, one or all, precede the closing scene. The sufferings of the patient are often most excruciating. Sometimes there is an itching sensation, with or without an eruption on the surface. Copious ptyalism has been occasionally observed. The urine is generally scanty, sometimes bloody or albuminous, and causes in its discharge a burning pain, which may extend to the whole genital organs, and is occasionally attended with priapism. The discharges are various in appearance; but from the stomach they are usually brown, and mixed with mucus or blood, and from the bowels are not unfrequently also bloody, and at a later period black and offensive.

Instead of the preceding symptoms, which are, for the most part, signs of an intense gastro-enteritis, the patient, in some rare instances, suffers little or no pain; even vomiting and purging may be absent; but prostration speedily supervenes, with faintness or syncope, and evidences of great nervous disorder, as delirium, coma, convulsions, or paralysis. Either the shock, made through the stomach upon the nervous centres, is so great as to prostrate the system below the point of inflammatory reaction, as sometimes happens from a violent blow on the epigastrium; or the poison is rapidly absorbed, and produces the effect directly upon the brain and heart. I am inclined to the former of these opinions.

In other cases, again, the gastro-enteritic symptoms are violent at first, but, passing off, leave the patient suffering with nervous affection, varying, according to Dr. Christison, from coma to a slight palsy of the limbs resembling that of lead, with intermediate grades of epileptic convulsion, tetanic spasm, or symptoms of hysteria or madness.

Arsenical palsy has been particularly investigated by M. Imbert Gourbeyre, of Clermont, in France, who states that it especially affects the lower limbs, but has a tendency to become general, and usually extends to the upper limbs, which, however, are less seriously affected, and first recover. The palsy may last from several months to years. it is attended with cramps, painful shocks, formication, etc., and may be partial or complete. it never follows the careful therapeutic use of arsenic however long continued, and occurs only when poisonous doses have been taken, differing in this respect from the palsy caused by lead. (Ann. de Thérap., 1858, p. 229.)

Death has happened so early as two hours after the taking of the poison; but generally it does not occur under eighteen hours, and sometimes not for several days.

The smallest quantity, I believe, known to have caused death, is two and a half grains of arsenious acid in a stout girl, and half a fluidounce of Fowler's solution, equivalent to about two grains of the acid, in the case of a woman.

The external application of arsenic is capable of producing poisonous effects; and it has been observed that the symptoms are the same as when it has operated through the stomach, including the vomiting, purging, abdominal pains, and other evidences of gastro-enteritis, as well as those which obviously spring from the absorption of the poison. Arsenious acid has been much used as an escharotic in cancerous affections; and numerous instances have occurred, in which, under such circumstances, it has been absorbed with fatal effect. it was at first thought that the liability to act in this way must be in proportion to the amount employed; and care was, therefore, deemed necessary not to apply it too freely to the surface to be destroyed; but experience seems to have shown, that the result is more likely to happen from small than large quantities. The more speedily and the more completely the surface is destroyed, the less will be its power of absorption, as dead flesh does not absorb; and the larger the quantity of arsenic employed, the more rapid and extensive must be the escharotic effect. it seems, therefore, that the result of experience, in this case, corresponds with what ought to be the conclusion of the judgment.