PREPARATIONS 495 



and are sometimes conjoined with cocaine. They pre- 

 vent prolapse of the iris in lesions of the cornea, 

 suoh as perforating ulcer, which is frequent in dogs. 

 In iritis mydriatics relieve congestion, and prevent or 

 break down adhesions between the iris and the capsule 

 of the lens, in such cases being generally alternated with 

 myotics. 



External topical applications often increase the effects pro- 

 duced by internal administration, belladonna plasters being 

 applied to the spine in tetanus, to the loins in irritation of 

 the kidneys or bladder, and to the throat in spasmodic 

 cough. Belladonna and atropine diminish congestion, 

 irritability, and pain in wounds, glandular swellings, and 

 injuries of the oesophagus, in rheumatism, and in those 

 hyper-sensitive conditions of the skin and muscles which 

 sometimes occur in horses and hounds from severe exer- 

 tion. To secure these results active preparations should 

 be applied or deeply injected, as near as possible to the 

 painful spot. In cases of emergency atropine sulphate, 

 administered hypodermically, is preferable to any bella- 

 donna preparation. 



DOSES, etc. Of the dried leaves horses and cattle take 

 3iv. to j. ; dogs, grs. v. to grs. x. The plant is seldom, 

 however, used in the crude form. 



An active green extract is made by the B.P. process, by 

 which 100 Ibs. fresh leaves and young branches yield 6 to 

 7 Ibs. of extract. The dose for horses is 3J- to 3ij- ; fc> r 

 cattle, 3ij- to ^iv. ; for sheep, grs. x. to grs. xxx. ; for dogs, 

 gr. i. to grs. v. In catarrhal and influenza cases the extract 

 is frequently prescribed with alcohol, ether or camphor. 

 A convenient electuary is made with liquor ammonii acetatis, 

 camphor, and treacle. 



The liquid extract, made with belladonna root and 

 rectified spirit, contains f grain of alkaloids in 110 minims. 

 The tincture is made with 2 ounces of liquid extract and 

 sufficient alcohol (60 per cent.) to form 30 ounces. The 

 B.P. tincture is now standardised to contain 0*05 per cent, 

 of alkaloids. The succus is obtained by bruising the fresh 

 leaves and young branches of belladonna, pressing out the 

 juice, and adding to every three volumes of juice one of 



