ABSORPTION BY THE RESPIRATORY TRACT 29 



rectum and floating colon rapidly absorb soluble medicines 

 and nutrients introduced by the anus ; and in gastric disease 

 rectal injection is often preferable to administration by the 

 mouth. Anaesthesia may be induced by chloral or ether 

 thrown into the rectum, but this method is unsatisfactory. 

 To ensure speedy absorption, and to prevent ejection of 

 medicines introduced through the anus, the solution should 

 be warm and concentrated to a few ounces. Larger quan- 

 tities will be retained and absorbed, but the injection should 

 not be bulky if immediate effects are desired. 



The respiratory tract furnishes probably the most actively 

 absorbent mucous surface in the body. Long used for 

 anaesthetic inhalations, it is occasionally employed for the 

 administration of remedies in cases of purpura hsemorrhagica 

 and parasitic bronchitis. Soluble drugs, introduced by in- 

 sufflation, are absorbed by the nasal lining, and medicines 

 in aqueous or alcoholic solution, not too concentrated, are 

 well borne and very rapidly absorbed by the tracheal, 

 bronchial, and pulmonary mucous membranes. Drugs 

 dissolved or suspended in oil are less tolerated, although 

 Levi, the chief authority on intratracheal administration, 

 maintains that small injections of oil are absorbed. Emul- 

 sions, however, are safer, so long as the quantity is small 

 and injection is made slowly. Intratracheal injections are 

 especially risky in bronchitis and pneumonia. Beyond a 

 slight gain in time, intratracheal injection has no advan- 

 tage over hypodermic administration, except in cases where 

 direct or local action is required (Guinard). 



Although seldom employed in practice for the administra- 

 tion of medicines, the female generative tract the uterus, 

 especially after parturition, absorbs very rapidly. Potassium 

 iodide has been found in the urine in from two to four 

 minutes after injection into the womb. The healthy vagina 

 absorbs very slowly, but when congested its absorbent power 

 is much increased. Absorption from the lining of the galac- 

 tophorous sinus of the cow's udder is fairly active. The 

 absorbent power of the conjunctiva is well known. Cocaine 

 appears to promote conjunctival absorption of solutions of 

 atropine, eserine, and strychnine, and of other drugs. 



The peritoneum, pleura, and the synovial membranes of 



