Fatal Period for Strychnia:—Shortest, five minutes (Dr. Gray on Strychnia, 1872, p. 55); longest, six hours after three grains (Taylor, Guy’s Hosp. Reports, Oct., 1857, p. 483); average, two hours. For nux vomica:—Shortest, fifteen minutes; longest, three hours or more (Guy); average, two hours (Taylor), one hour (Guy).
Symptoms commence at various intervals after taking, according to dose, form, and constitution. The beginning may be (1) almost immediate (Mad. Merghelynk, 1870, Taylor’s Med. Juris., p. 408), (2) in five minutes (case of Dr. Warner, also Dr. Gray on Strychnia, 1872, p. 55), (3) in fifteen minutes (trial of Dove, p. 242), (4) about an hour (Palmer’s trial, p. 102), (5) forty minutes (Lond. Med. Repository, xix., 448), up to two and a half hours (Wormley, Microchemistry of Poisons, p. 538). Hence no conclusion can safely be drawn from this feature (see Dr. Letheby’s evidence in the Palmer trial, p. 166). Probably Dr. Todd’s statement in the same trial is the most correct average:—“Symptoms in ten minutes, if in solution and a large dose; otherwise in a half to one hour.”
The different action of powder and solution is shown in the following experiments on two full-grown rats:—
1. Half a grain of powdered strychnia—First convulsion in twenty minutes, death in two and a half hours.
2. Same quantity dissolved in sufficient acid—Effect almost immediate; death in half an hour. In the stomach, liver, and brain, strychnia was separately detected.
Pills, especially if hard, would be very slow in action. The most intense effect is produced by hypodermic injection.
Symptoms in Man:—Bitter taste in the mouth, feeling of suffocation, jerkings and twitchings of head and limbs, then tetanic convulsions of nearly all the muscles. Body stretched out stiff, finally arched back so as to rest on the head and the heels (opisthotonos), spasmodic and difficult breathing, usually a peculiar grin (risus sardonicus). After a time the jaw becomes tightly fixed (trismus or lockjaw), the fingers are clenched, the feet arched inwards (incurvated), the eyes prominent and staring. The spasm lasts from a half to two minutes, then there is an interval of comparative rest. The pupils are generally dilated during the fit, contracted in the interval. A touch, a change of position, or a sudden noise, will usually cause a renewal of the spasm. In severe cases the convulsions recur at diminishing intervals, increasing in violence till death occurs from exhaustion or suffocation. Vomiting is very rare. Taylor says “the jaw is not always fixed during a paroxysm: the patient can frequently speak and swallow” (Med. Juris., 1873, p. 404). Woodman and Tidy (Forens. Med., 1877, p. 330) say that this symptom is invariably present. Guy and Ferrier are cautious, and state that the effort to drink often causes rigid spasms of the jaw, but that the “jaw is not always fixed, even in the fit” (Guy and Ferrier’s Forens. Med., 1881, p. 573). On the whole, fixing of the jaw is usual but not invariable. In the Palmer and Dove trials the patients spoke or shrieked during the paroxysms.
As to impatience of touch, Mr. Morley’s dictum in the Dove trial expresses the truth: “Not shrinking from touch is consistent with strychnia, but a desire not to be touched is an indication of it. Several cases of strychnia had desired to be rubbed.” See also the cases of Mrs. Smyth and Mr. Clutterbuck, pp. 122 and 123.
Consciousness, in the immense majority of cases, is preserved to the last. If, as in Mrs. Dove, insensibility occurs, it is due to the exhaustion. In this trial Dr. Christison said “it is unusual to be insensible before death from strychnia.” Farquharson (Therapeutics, p. 264) states that “the cerebral functions remain unimpaired almost up to the close.” This is agreed to by all authorities.