196 PHYSOSTIGMINE. 



PHYSOSTIGMINE. 



Physostigmine (Ci5H 2 iN 3 O3 = 273.20), or Eserine, is the principal alkaloid of 

 Physostigma venenosum, an African plant. 



Pharmacodynamics. 



Central Nervous .System. Physostigmine produces a depression of the cord and 

 medulla; later, of the higher centers. 



Muscular System. Striped muscle is disordered, unstriped muscle is stimulated, 

 through irritation of the peripheral nerve filaments. 



Respiration. Accelerated at first by peripheral irritation; later, slowed and weak- 

 ened by centric depression. 



Heart is slowed by both centric and local action. 



Blood-pressure is raised by centric action and by local constriction of the arterioles. 



Eye. Pupil is contracted through stimulation of the filaments to the motor oculi 

 muscle. Ciliary muscle is stimulated. 



Alimentary Tract. Activity of the musculature is stimulated through irritation 

 of the myoneural terminations. 



Secretory glands are all greatly stimulated through irritation of the peripheral 

 filaments. 



Metabolism. Apparently little affected. 



Temperature. No constant change noticeable. 



Absorption is fairly rapid. 



Excretion. Some physostigmine escapes in the urine, but the greater part is 

 destroyed in the tissues. 



Symptoms. 



Therapeutic Doses. Toxic Doses. 



Salivation. Tremors. 



Perspiration. Muscular weakness. 



Slightly slower heart. Salivation and lachrymation. 



Gastro-intestinal uneasiness. Giddiness. 



Dyspnea. 



Excessive perspiration. 



Vomiting and gastralgic pains. 



Myosis. 



Copious, watery stools. 



Weak, slow heart. 



Collapse. 



Respiratory failure (centric). 



Therapeutics. 



Physostigmine is used to promote peristalsis in threatening atony. In ophthal- 

 mic work it is used to reduce the intraocular pressure attendant on glaucoma. 



Dosage. 



Extractum Physostigmatis, 0.004 to 0.008 Gm. 

 Tinctura Physostigmatis, 0.3 to 1.2 mil. 

 Physostigminse Salicylas, o.ooi Gm. 

 "Eserine" is another name for Physostigmine. 



