148 DEPRESSANTS TO CENTRAL NERVOUS SYSTEM 



Preparations and Doses. 



Narcotic (H. & C. sijss— iv (75—125) 

 (per OS. or rectum. 

 Chloralum Hydratum 



Sedative (H. & C. §j— ij ; 30.— 60. 

 (D. gr. V— ix; 0.3—4. 



Chloral Camphor N. F. Equal parts of chloral hydrate and 

 camphor. Used as a counterirritant. 



External and Local Action, Locally it is anesthetic, anti- 

 septic and irritant. It is especially irritant to mucous membranes 

 and raw surfaces, so that when strong solutions are brought into 

 contact with wounds or mucous membranes sloughing follows. On 

 account of this action it is not suitable for hypodermic medication 

 and even when given per os care must be taken to dilute it suffi- 

 ciently so that it will not injure (burn) the throat and esophagus. 



Digestive System. Small doses may be slightly sedative or 

 anesthetic to the stomach although causing a sensation of burnijig 

 in the throat, together with salivation. Large doses may irritate 

 the stomach and cause nausea, vomiting and purging. It is also 

 an antiferment. 



Nervous System. The principal action of the drug is seen 

 upon this system. In moderate doses it depresses the cerebrum 

 without appreciably affecting the respiratory and circulatory sys- 

 tems and produces a deep sleep lasting for several hours. The 

 narcosis is produced quite promptly and lasts for several hours with- 

 out causing digestive or other disturbances. Larger doses depress 

 all the centers, including the motor, cause deeper sleep, lessen the 

 reflex excitability of the spinal cord and depress the respiratory and 

 vasomotor center in the medulla. In this way it may serve as an 

 anesthetic or narcotic for operations. It has no eft'ect upon the 

 peripheral nerves. Toxic doses produce all the symptoms seen in 

 chloroform poisoning. 



Respiratory System. There is no effect from moderate doses. 

 Large doses render the respirations irregailar and feeble while toxic 

 doses paralyze the respiratory center. Death is due to respiratory 

 paralysis. 



Circulatory System. This system is not affected by small or 

 moderate doses. Larger doses may accelerate the heart for a short 

 time but this is soon followed by depression so that the pulse becomes 

 slower, softer and weaker. The peripheral arteries are dilated by 

 direct depression on the arterial muscles. Toxic doses lower the 

 blood pressure by direct depression of the cardiac muscle, by de- 

 pressing the vasomotor center and by depression of the arterial 

 muscles. 



