4^16 VEGETABLE DRUGS 



ination and accamulation of the drug in the system. The 

 cumulative action of digitalis is chiefly due to the latter 

 cause. It should never be administered in full medicinal 

 doses uninterruptedly for any considerable length of time. 



Toxicology. — Poisoning may occur from large single 

 doses within 3 to 10 hours of their ingestion, and last for 16 

 or more hours with a fatal result; or may appear suddenly 

 after the administration for several days of large medicinal 

 doses (cumulative action). A minimum fatal dose for the 

 horse is about 3 vi. of digitalis, or gr.i.ss. of Homolle's digi- 

 talin. For dogs, 3 i- of digitalis, or gr.^ of digitalin. The 

 symptoms exhibited are chiefly concerned with the digestion 

 and circulation. They consist in dulness, lassitude, loss of 

 appetite, nausea, flatulence, diarrhoea, infrequent, full pulse 

 (reduced 6-10 beats in the horse), and contracted pupils. 

 There is vomiting in dogs. In fatal cases these symptoms 

 are followed by severe colic and tympanites; rapid, feeble, 

 dicrotic, irregular or intermittent pulse (120-140 in horses), 

 while the heart may be heard and felt beating wildly and 

 strongly, and a systolic blowing murmur can frequently be 

 detected. This is due to mitral or tricuspid regurgitation 

 caused by irregular contraction of the columnse carnse. The 

 pulse is imperceptible because of the failure of the heart 

 to fill the vessels. The extremities are cold, the eye is pro- 

 truding, and salivation occurs. Bloody diarrhoea is very 

 often present and the urine may be suppressed. The breath- 

 ing finally becomes difficult and death ensues within a few 

 hours, or as late as several days. 



Treatment — Evacuation of the stomach and bowels. 

 Tannic acid, as a chemical antidote, alcohol, opium, and 

 aconite, which is the physiological antagonist in depressing 

 the action of the heart and lowering blood tension. In 

 addition, external heat should be applied and complete 

 quiet and rest secured. 



Administration. — ■ In view of its slow absorption and 

 elimination digitalis should not be given oftener than once 

 in six, eight, or even twelve hours. Very large doses may 



