LEAD.

509

simple and consistent with analogy, to admit that these preparations areof themselves capable of producing colic, than to assume that theyundergo the changes here supposed. Moreover, in some instances inwhich colic was produced, it is unlikely that these changes could haveoccurred, owing to the excess of acid taken with the salt of lead.

Uses. —The uses of the preparations of lead may be in part inferredfrom the foregoing account of their effects. These agents are employedwhen we wish to constringe the capillary vessels and to diminish theirvital activity. Thus we administer them internally to check excessivesecretion and exhalation, as in catarrhal affections of the mucous mem-branes of a chronic nature; in profuse secretion of pus; in sanguineousexhalations from the mucous membranes ; and in colliquative sweating.They have also been applied, in some instances with success, in certainchronic affections of the nervous system, as epilepsy; but the practice isaltogether empirical, as we have no rational principles to guide us inusing them. As topical remedies, we employ the preparations of lead todiminish vascular excitement, to allay preternatural heat, and to checkexcessive secretion. Thus we apply them to inflamed parts to promoteresolution, and to ulcers and other secreting surfaces as astringents ordesiccants. During the internal employment of lead, attention must bepaid to the condition of the stomach and bowels, as we find the traces oftheir injurious effects in these organs. Constipation is a very frequentresult of their medicinal employment. Loss of appetite, indigestion, andgriping pains, are also often noticed. The tendency to colic is dimi-nished, according to Dr. A. T. Thomson, by conjoining acetic acid.

Antidotes. —Poisoning by lead usually puts on one of three forms—irritant poisoning, lead colic, and paralysis.

1. Irritant poisoning. —Administer diluents holding in solution somesulphate (as sulphate qf soda, of magnesia, or of potash or alum), so thata sulphate of lead may be formed. If vomiting have not already comeon, tickle the throat, and administer emetics of the sulphate of zinc or ofcopper, or the stomach-pump may be employed.

2. Lead colic. —Here the best remedy is alum ( vide pp. 372, 373).But in this country lead colic is frequently treated by the combined useof purgatives and anodynes, the purgatives being either castor oil or saltsand senna, the anodyne being opium. When the vomiting is verytroublesome, and liquid medicines do not remain on the stomach, we maygive the compound extract of colocynth, with opium, in the form of pill.In several cases in which the pulse was full and strong, the face flushed,and the tongue furred and dry, I have used blood-letting with evidentadvantage. The sulphates have been recommended, as also mercury.

3. Lead paralysis. —Nux vomica, and its active principles—strychniaand brucia, are perhaps of all internal remedies most deserving of trial,because of their specific effect on the spinal marrow; and the chance oftheir success is, of course, much increased by the circumstance of therebeing no discoverable lesion of this portion of the nervous system.Mercury has been recommended by Dr. Clutterbuck. Various localmeasures have been tried, but without much benefit; for example,electricity and irritants (such as ammonia and cantharides).