STRYCHNIA. 289 



Internally. Nux vomica and strychnia possess all the pro- 

 perties of bitters as described under Calumba (page 181), to which 

 the student will refer. Their use is not different from that of 

 other bitters, excepting that whilst they are unpleasant from 

 the intensity and persistency of their taste, and the absence of 

 all covering flavour, they are very convenient on account of 

 their small bulk. The Tincture of Nux Vomica is to be pre- 

 scribed with alkalies, the Liquor Strychniae with acids. 



Strychnia is believed to increase the peristaltic action of 

 the intestines, and is therefore combined with purgatives, 

 especially aloes, for chronic constipation from atony of the 

 bowel. 



2. ACTION ON THE BLOOD. 



Strychnia enters the blood from mucous surfaces, or when 

 given hypodermically. Here it affects both the red corpuscles 

 and the plasma, reducing the absorptive power of the former for 

 oxygen, and the discharge of carbonic acid from the latter. 

 These effects are not, however, the cause of the specific action 

 of the drug immediately to be described. 



3. SPECIFIC ACTION. 



Strychnia quickly finds its way into the viscera, especially 

 the nervous system, and is peculiar in remaining so long within 

 them, that it is not wholly excreted for several days. Enter- 

 ing rapidly, and disappearing slowly, the alkaloid accumulates 

 in the body if the dose, however small, be very frequently re- 

 peated, and is said to have a " cumulative action." 



In medicinal doses, strychnia produces a tonic influence, 

 as described under Calumba and Quinia, with a sense of in- 

 creased strength and spirits. Therewith its specific action is 

 soon developed, namely, increased sensibility of touch, sight, 

 and hearing, with some disorder of the senses, such as of colour, 

 vision, and smell. Repeated or larger doses next lead to sudden 

 twitchings of the muscles of the limbs, a constricted feeling in 

 the chest, and some dysphagia, with a sense of anxiety. 

 Poisonous doses produce violent convulsions, and rapid death 

 by exhaustion and asphyxia, from spasmodic arrest of the 

 respiratory muscles. The phenomena resemble tetanus, but 

 differ from it in the complete relaxation of the muscles between 

 the convulsive seizures, in the great rapidity of their course, 

 and in the comparative absence of trismus (lock-jaw). 



Careful analysis resolves the phenomena of strychnia 



poisoning as follows, and enables us to understand its action in 



medicinal doses. The convolutions are unaffected. The motor 



centres of the cord are powerfully irritated by toxic doses, and 



T 8 



