Aids To Forensic Medicine And Toxicology Part 20

x.x.xVII.--ANTIPYRINE, ANTIFEBRIN, PHENACETIN, AND ANILINE

Many of the synthetical coal-tar products now so largely employed as a.n.a.lgesics are powerful toxic agents.

=Phenazone, Antipyrine, or a.n.a.lgesin=, is a complex benzene derivative prepared from aniline, aceto-acetic ether, and methyl iodide. It is in colourless, inodorous, scaly crystals, which have a bitter taste. It is soluble in its own weight of water.

_Tests._--Can be extracted from an alkaline solution of chloroform. The residue left on the evaporation of chloroform should be employed for testing. If heated with strong nitric acid and allowed to cool, a purple colour is produced. Ferric chloride gives a blood-red coloration, destroyed by the addition of mineral acids.

_Treatment._--Stimulants freely, inhalation of oxygen, patient to be kept in the rec.u.mbent position.

=Acetanilide, Antifebrin, Phenylacetamide= (a const.i.tuent of 'Daisy' or 'headache' powders), is obtained by the interaction of acetic acid and aniline. It is in colourless, inodorous, lamellar crystals, which have a slight pungent taste. It is insoluble in water.

_Tests._--May be extracted from acid solutions by ether or chloroform.

If heated with solution of pota.s.sium hydroxide, odour of aniline is given off; if liquid, when it is warmed with a few drops of chloroform, a penetrating and unpleasant odour of isocyanide.

_Treatment._--Emetics, stimulants, inhalation of ether, rec.u.mbent position.

=Phenacetin, Phenacetinum=, is produced by the interaction of glacial acetic acid and para-phenetidin. It is in white, tasteless, inodorous, glistening, scaly crystals, insoluble in water. Of all the members of the group, it most rarely produces toxic symptoms.

_Treatment._--As for the other members of this group.

=Exalgin, Aspirin, etc.=, as well as the above, may all act as poisons to certain persons, and even small medicinal doses may cause serious and even fatal consequences.

_Symptoms_ (more or less common to all).--Nausea, vomiting, hurried respiration, marked cyanosis, syncope. Persistent sneezing and widespread urticaria may be present; collapse.

=Aniline= is an oily liquid, heavier than, and not soluble in, water. It is colourless or reddish-brown; it has a peculiar tar-like odour; it is soluble in alcohol, and forms a soluble sulphate with sulphuric acid. A solution of bleaching-powder gives with solution of the sulphate a purple colour changing to red-brown.

_Symptoms._--Nausea, vomiting, giddiness, intoxication, drowsiness, gasping for breath, feeble pulse, and marked cyanosis. In its _industrial use_ it may act as a poison either by inhalation of the fumes or by absorption through the skin. The symptoms then are mainly those of peripheral neuritis with blindness.

_Fatal Dose._--About 6 drachms.

_Treatment._--Wash out stomach; stimulants, artificial respiration, inhalation of oxygen, transfusion.

=Nitro-benzol= (Artificial Oil of Bitter Almonds).--It is used in perfumery, but is very poisonous when swallowed, or inhaled, or absorbed through skin. It is used in the manufacture of aniline dyes, and may act as an industrial poison. The symptoms closely resemble those of aniline poisoning, but there is perhaps greater mental confusion.

_Fatal Dose._--Eight to ten drops have caused death.

_Treatment._--Emetics, stimulants, transfusion of saline or blood, pituitrin, strychnine, or digitalin hypodermically.

=Nitroglycerine= gives rise to intense and persistent headache ('powder headache'). Throbbing and pulsation of all the arteries in the body; flushing of the face and collapse may follow.

=Dinitrobenzene= causes symptoms resembling nitro-benzol poisoning, and when acting as a chronic poison gives rise to weakness, jaundice, peripheral neuritis.

x.x.xVIII.--SULPHONAL, TRIONAL, TETRONAL, VERONAL, PARALDEHYDE

These are dangerous drugs. The ordinary _symptoms_ of the group are noises in the ears, headache, vertigo, inability to stand or to walk properly, insensibility, and cyanosis.

The most interesting point is the condition of the urine. In cases of poisoning it is dark or reddish-brown in colour, due to the presence of _haematoporphyrin_. It contains alb.u.min and casts, but no red corpuscles.

In cases of haematoporphyrinuria the prognosis is bad, and it is said that these cases invariably end fatally.

_Treatment._--In an ordinary case emetics, strong coffee, hypodermic injections of strychnine, saline injections, and transfusion.

Cases of chronic poisoning from the 'als' are not uncommon, and are increasing in frequency. Hypnogen is apparently identical with veronal.

All the above-named aniline derivatives are included in Part I. of the scheduled poisons.

x.x.xIX.--CONIUM AND CALABAR BEAN

=Conium Maculatum= (Spotted Hemlock).--All parts of the plant are poisonous, often mistaken for parsley. Contains the poisonous principle _coniine_, a volatile liquid alkaloid with a mousy smell; insoluble in water; soluble in alcohol, ether, and chloroform. It also contains methyl coniine.

_Symptoms._--Dryness of throat, headache, dilated pupil, dysphagia, loss of muscular power, pa.s.sing into complete paralysis. Delirium, coma, and convulsions, occasionally.

_Post-Mortem Appearances._--Congested brain and lungs; redness of the mucous membrane of the stomach. The stomach and intestines should be examined for fragments of the leaves and fruit, recognized by their microscopical appearances.

_Treatment._--Emetics, tannic acid or gallic acid. Diffusible stimulants.

_Method of Extraction from the Stomach._--Use Stas-Otto process.

_Tests._--The mousy odour. Deepened colour and dense white fumes with nitric acid. Pale red, deepening, with hydrochloric acid.

There are several other umbelliferous plants which are poisonous. The water hemlock (_Cicuta virosa_) produces symptoms not unlike those of hemlock; it has been mistaken for parsnip and celery. It contains an active principle, _cicutoxin_, which in some respects is allied to strychnine and picrotoxin. The fool's parsley, or lesser hemlock (_aethusa cynapium_), is another member of this group, although doubt has been expressed as to whether it is really poisonous. The water dropwort (_Oenanthe crocata_) is undoubtedly poisonous, especially to cattle. In man it produces abdominal pain with diarrhoea and vomiting; dilated pupils, slow pulse, and cyanosis; delirium, insensibility, and convulsions. The post-mortem appearances are not characteristic, but the stomach and intestines should be examined for portions of the plant.

=Calabar Bean or Physostigma.=--The bean of _Physostigma venenosum_ contains the alkaloid physostigmine or eserine, with the antagonistic alkaloid calabarine.

_Symptoms._--Vomiting, giddiness, irregular cardiac action, contraction of the pupils, paralysis of lower extremities, and death from asphyxia.

_Treatment._--Emetics; hypodermic injection of 1/50 grain sulphate of atropine, repeated if necessary.

_Method of Extraction from the Stomach._--Use Stas-Otto process.

_Test._--The contraction of the pupil which it causes.

XL.--TOBACCO AND LOBELIA

=Tobacco.=--_Nicotiana tabac.u.m_ owes its poisonous properties to its alkaloid nicotine, a volatile, oily, amber-coloured liquid, with an acrid taste and ethereal odour; soluble in water, alcohol, ether, and chloroform. The drug has an intense depressant action on the heart and respiratory centre.