174 DEPRESSANTS TO PERIPHERAL NERVES 



B. Those which stimulate, pilocarpine, physostigmine and are- 

 coline. 



A. DRUGS DEPRESSING THE PERIPHERAL NERVES 

 BELLADONNA OR ATROPINE GROUP 



The belladonna or atropine group of drugs consists of a number of 

 alkaloids of quite similar composition, which are found in a large 

 number of plants belonging to the potato family or solanacese. Eor- 

 merly each alkaloid received a specific name according to the plant 

 from which it was obtained, but more recent investigation has shown 

 that this group takes in several alkaloids and that each occurs in all 

 the plants, but in variable proportion. The principle members of 

 this group are : 



Belladonna Stramonium 



Hyoscymus Scapola 



Similar alkaloids may also be obtained from the following plants : 

 Duboisia myoporoides, and Mandrangana automnalis. 



BELLADONNA 



Synonym. Deadly nightshade 



Parts Used. The leaves, folia, and roots, radix, of Atropa hel- 

 ladonna of central and southern Europe and western Asia and 

 grown for the drug trade in England' and Germany. Tradition has 

 it that the drug was so named from the fact that it was used in 

 early times by the ladies to produce lustre to the eyes. The term 

 literally means " Beautiful Lady." 



Active Principles, Belladonna contains two alkaloids. Atro- 

 pine and hellodonnine, which is identical with hyoscyamine. In 

 fact, recent investigations tend to show that atropine is an artificial 

 alkaloid of hyoscyamine and that the latter is the true or natural 

 alkaloid. Chemically atropine is a compound of the isomers, dextro 

 and levo hyoscyamine, into which it separates when dissolved in 

 water, while hyoscyamine is really levo hyoscyamine and is easily 

 changed to dextro hyoscyamine. 



Preparations and Doses. 



Belladonna Folia. H. 3ij— viij ; 8. — 30. ' D. grs. ij — v ; 



•0.13—0.3. 

 Tinciura Belladonnce Foliorum. D. Til v — xxx; 0.3 — 1.3. 

 Fluidexiractum Belladonnce, Radieis. H. .5j — ij ; 4 — 8. D. 



nij— iij ; 0.65—0.2. 

 Extradum Belladonnce Foliorum. H. gr. x — xx; 0.6 — 1.3. 

 D. gr. Vs—Vz ; 0.008—0.03. 



