172 CANINE MEDICINE AND SURGERY 



Absorption. — The rapidity with which poisons 

 are absorbed depends to a great extent on the 

 poison itself, the portal by which it gains entrance 

 to the animal's economy, the condition of the diges- 

 tive tract — whether full or empty, and also the 

 nature of the stomach contents. For instance, the 

 unbroken skin will easily and rapidly absorb gases, 

 but solids or liquids hardly at all; on the other 

 hand, irritated or woundca skin becomes very ab- 

 sorbent. Again, an empty stomach will absorb 

 far more readily and rapidly than a full one, and 

 yet again, the digestive tract just after a meal 

 of fatty substances, even milk, is far more impene- 

 trable than when a meal with no fat has been par- 

 taken of. The exception to this is phosphorous, the 

 absorption of which is accelerated by oils and fats. 



Elimination. — Poisons are eliminated in the excre- 

 tions. Nearly all mineral poisons are eliminated 

 through the kidneys, some by the bowels. Gases, 

 vapors, and volatile poisons are eliminated by the 

 lungs. Some poisons undergo changes during elimi- 

 nation, others are eliminated unaltered. 



Treatment. — The main objects to be attained are 

 to delay or prevent absorption, to neutralize the 

 poison or render it insoluble, to eliminate from the 

 system both what is absorbed and what is unab- 

 sorbed, and to counteract the eflfects produced by 

 the poison absorbed and the resulting lesions. 



The first can be accomplished by emetics and 

 purgatives, the former by reason of their rapidity of 

 action being the most valuable. Purgatives are 

 chiefly valuable when combined with agents that 

 retard absorption or with those that unite with 

 poisons and form insoluble or inert compounds. 

 Antidotes act in three ways : they neutralize the 

 poison, render it insoluble, or arrest its injurious 

 effects. 



