54 



obviously by no means easy to draw a broad line of demarca- 

 tion between these two divisions, except in so far as the first 

 group comprises most purgative drugs. Many drugs were 

 believed to act both as vermifuges and vermicides ; whilst, 

 in the case of others, those who recommend them do not 

 know, or, wisely, do not care to explain, in what manner 

 the drugs which they favour produce the desired effect 1 . 



Mineral Purgatives as Anthelmintics. 



Foremost among Vermifuges rank the " saline " purgatives ; 

 and the drugs commonly prescribed for Oxyuris are the more 

 drastic members of this class, such as the alkaline car- 

 bonates (sodium, potassium and ammonium), the oxide and 

 carbonate of magnesium, the sulphates of sodium, potassium 

 and magnesium, and the bi-tartrate of potassium. These 

 substances are said to act by increasing the flow of fluid from 

 the glands of the intestinal walls ; and, though they are useful 

 aperients, there is no good ground for crediting them with 

 any special action upon threadworms, which, indeed, they 

 commonly fail even to expel. 



Other mineral substances which enjoy a reputation as 

 anthelmintics are sulphur, and calomel, to which specific 

 virtues have been ascribed, in addition to their purgative 

 action. But sulphur, especially in large doses, is by no means 

 harmless, and often causes headaches and nervous depression. 

 On the other hand, calomel, or subchloride of mercury, by in- 

 creasing the flow of bile becomes a powerful purgative, but 

 it frequently sets up symptoms of poisoning, and its use, 

 particularly in the case of children or other weak subjects 2 , 



1 PARACELSUS recommends dried 2 The danger of mercurial vermi- 



and powdered worms taken in cides has long been recognised : 



goats' milk ! " . . . verum alios " Ad mercurialia, tamquam sacram 



vermes omnes in hominibus ortum anchoram, confugiunt practici, quae 



et sustentationen habentes, quo- certe, in siccioribus, quibus humor- 



cunque nomine vocentur, ubi siccati um tenuitas et acrimonia molestiam 



fuerint, pulverati, necnon hominibus creant, minime vermes necant, 



intrinsecus administrati cum quovis sed universum corpus, attenuando, 



liquore : in caprino lacte melius : magis humores subducunt, atque 



vermes omnes ad hunc modum ita emaciant, ut omnes ejus func- 



expellunt ab intestinis et stomacho tiones pessundentur." (VAGHI, G., 



per secessum." (PARACELSUS, T., De insectorum in corpore humano 



op. cit., p. 412.) genitorum varia forma et indole, 



Vitembergae, 1741, pp. 73, 74.) 



