364 MATER i A MEDIC A AND THERAPEUTICS. 



ACTION AND USES. 



The physiological action of colchicum is imperfectly 

 understood, and affords but a partial explanation of its 

 empirical use. 



Given internally it is a gastro-intestinal irritant, acting as 

 an emetic and purgative in full doses, the stools containing 

 a decided increase of bile, partly referable to a direct 

 cholagogue effect of the drug. Colchicin appears to enter the 

 blood and tissues, and here acts chiefly upon the central 

 nervous system. The convolutions and spinal cord are 

 depressed, large doses causing loss of sensibility and conscious- 

 ness, and diminished reflex excitability. The peripheral 

 sensory nerves are also paralysed, but the motor nerves and 

 muscles remain unaffected. The respiratory centre is lowered 

 in activity, and death occurs by asphyxia. The heart is 

 weakened, the pulse even becoming intermittent ; but this 

 effect is believed to be entirely secondary to the disturbance of 

 the respiration. The kidneys are hypergemic, and the amount 

 of urine diminished ; the uric acid and probably the urea 

 are reduced in quantity. The skin perspires more freely. 



Colchicum is chiefly used to relieve the pain and inflamma- 

 tion, and shorten the duration, of acute gout, for which 

 purpose it is usually given in doses short of producing the 

 above physiological effects, so that the mode of its action is 

 quite obscure. It is most successful in first attacks in young 

 robust subjects ; less useful, and to be used with caution, in 

 the chronic gout of old weakly individuals ; and occasionally it 

 completely fails to afford any relief. It is generally prescribed 

 with alkaline purgative salines. In some acute gouty affections 

 of other parts than the joints, such as bronchitis, hepatic 

 congestion, neuralgia, and urethritis, colchicum occasionally 

 relieves. It is worse than useless in rheumatism. The extract 

 may be added to purgative pills as a cholagogue. 



PALMACE^}. 



Areca ARECA NUT. The seed of Areca 

 Catechu, the Betel Nut Tree. Imported from the 

 East Indies. 



Characters. The nuts are about the size of a nutmeg, but 

 less wrinkled and more globular, and not aromatic ; reddish- 

 brown externally, having a flattened base and somewhat conical 

 apex. The interior is hard, dark brown, finely marbled with 

 white. Inodorous, with astringent taste. 



