Fatal Period.—May occur in a few hours, or days, or after months; also after the use of the drug has been discontinued.
Chemical Analysis.—Sulphonal is very stable, and is unaffected by boiling alkalies or by concentrated nitric or sulphuric acids. From its solution in concentrated sulphuric acid it may be recovered by dilution. It is easily recovered from the body after death, as its stability prevents its decomposition. It is isolated from organic matter by treatment with alcohol, evaporation, and extraction of the residue with hot water, evaporation and final extraction with ether.
Tests.—1. Heated in a test tube with powdered charcoal, sulphonal forms mercaptan, acetic acid, formic acid, and sulphur dioxide. The offensive odour of mercaptan may be noted, and the vapours will change blue litmus paper. Sulphur dioxide may be shown by its bleaching action on a piece of filter paper moistened with blue starch iodide and suspended in the mouth of the tube.
2. When melted with potassium cyanide, sulphonal develops a mercaptan odour, and potassium sulphocyanate is formed at the same time. A blood-red colour is therefore produced on the addition of ferric chloride to a solution of the residue in water. Great care must be exercised in the carrying out of this test, as it is somewhat dangerous to the experimenter.
Treatment.—The stomach should be washed out in order to remove any drug unabsorbed. Diuretics, purgatives, and general stimulants given, such as strychnine, hot coffee, &c.
TRIONAL AND TETRONAL
These compounds are very similar in both their chemical and physiological properties to sulphonal, but both have a bitter taste. Both have caused fatal poisoning, the symptoms being very similar to those caused by sulphonal.
VERONAL
Veronal, a synthetic compound, is a white crystalline powder about four times as powerful as sulphonal, very slightly soluble in water, more soluble in hot water, and in alkaline solutions, and absorption takes place from the intestine.
Symptoms.—In moderate doses it produces sleep without subsequent depression, and does not affect temperature or respiration. In larger doses it may cause erythema and constipation, with alternating semi-coma and delirium. During the last few years fatal cases of poisoning have become rather frequent.