Peruvian bark is slightly irritant to the parts with which it is brought into contact, and sulphate of quinia more so. Hence, the powdered bark was formerly sprinkled over indolent, flabby, and sloughing ulcers; and the decoction was employed as a gargle in gangrenous ulceration of the fauces. The remedy was supposed to be peculiarly useful in mortifying parts, from the fact that bark has some influence in retarding the putrefaction of animal matters; but it is now well understood that the antiseptic property, though it may tend to prevent the decomposition of parts already dead, and, therefore, to correct fetor in sloughing ulcers, has no influence whatever, as such, on the process of mortification; and consequently, if Peruvian bark is useful in such cases, it is by supporting the vital actions through its tonic, and not through its antiseptic powers.

The effect of the medicine in giving tone to the stomach may be considered as, in some degree, the direct result of its local application to the gastric mucous membrane; and, in the same way, it may do good in ulcerative conditions of the bowels, in which a local stimulation is desirable; as in some cases of chronic diarrhoea and dysentery, and the advanced stages of enteric or typhoid fever.

As quinia passes unchanged through the kidneys, and is thus brought into immediate contact with the urinary passages, it must exert upon these its ordinary local stimulation, and may thus prove useful in certain cases of chronic inflammation and ulceration of the pelvis of the kidneys, the ureter, and the bladder, and in retention and incontinence of urine dependent on debility of the bladder or its sphincter.

Sulphate of quinia may be used locally for the same purposes as the bark, but, in this case, should be much diluted with some unirritating material.