HYOSCYAMUS 389 



odorless and having an acrid, slightly bitter taste. Soluble in 1.5 parts of water, 

 and in 20 parts of alcohol; slightly soluble in chloroform. 



Dose.—H., gr. ya-% (.001-.016) ; D., gr. 1/100-1/30 (.0006-.002). 



Action Internal. — The action of hyoscyamus is a resultant of that of 

 its two alkaloids, hyoscine and hyoscyamine. The latter is practically 

 atropine, except that its mydriatic action is shorter. Hyoscine, in poi- 

 sonous doseS; is a powerful depressant to the cerebrum, respiratory centre, 

 spinal reflex centres, and motor tract. It differs from atropine in being 

 a cerebral sedative, and in its, greater paralyzant action upon the spinal 

 cord. The tetanic stage succeeding spinal paralysis, observed in atropine 

 poisoning, does not ensue with hyoscine. The latter alkaloid slightly 

 depresses and slows the heart, and does not paralyze the vagus termina- 

 tions, nor depress the motor and sensory nerves or muscles. The circula- 

 tion is but slightly influenced, and vasomotor depression occurs only in 

 the latter stage of lethal poisoning. Death occurs from paralysis of the 

 respiratory centres. Poisoning in animals is exhibited by loss of muscular 

 power, slowing and failure of respiration, dryness of the mouth, stupor 

 and asphyxia. The pulse may be infrequent, the pupils are dilated and 

 the skin is moist rather than dry. Delirium and convulsions sometimes 

 occur in man. The effect of the combined action of hyoscyamine and 

 hyoscine in hyoscyamus is shown when we compare the drug with bella- 

 donna. Hyoscyamus is more of a cerebral sedative and hypnotic, and 

 less of a heart and respiratory stimulant. It is said to possess more power 

 in overcoming spasm, and griping of cathartics, and in aiding intestinal 

 movement. Hyoscyamus is also thought to exert a more pronounced 

 antispasmodic action than belladonna upon the smooth muscles of the 

 bladder and urethra. 



Uses. — Hyoscyamus is generally applicable in the same disorder? for 

 which belladonna is indicated. In relieving some sorts of spasm, hyo- 

 scyamus is more eflicient than belladonna, as in spasmodic colic, spasm 

 of the bladder, and griping caused by cathartics. Tetanus, chorea, and 

 epileptic convulsions in dogs, are benefited by henbane, but the drug does 

 not possess a curative action. Hyoscyamine may be combined to ad- 

 vantage with strychnine, subcutaneously, in impaction of the bowels in 

 horses. The former drug relaxes intestinal spasms, and assists the stimu- 

 lant action of strychnine upon the intestinal muscle. Repeated small 

 doses of oil will facilitate peristalsis in this condition. Hyoscine hydro- 

 bromide is indicated in spasmodic affections and in nervous and sexual 

 excitement. It is a powerful drug and should be employed at the outset 

 in small doses. To avoid contamination with hyoscamine is difficult, and 

 a pure preparation is to be recommended. Hyoscine has not been em- 

 ployed to any extent in veterinary practice. It is used in human medi- 

 cine as a hypnotic and sedative in mania and delirium of the insane. It 

 causes no unpleasant after-effects. Scopolamine is identical with hyo- 

 scine and is so named because obtained from Scopola atropoides. Scopo- 

 lamine, or hyoscine, with morphine under the skin have been employed to 

 some extent as general anesthetics in human surgery to replace ether or 

 chloroform. To aid in obstetric operations in cows, as in replacing an 

 inverted uterus, scopolamine hydrobromide (gr.1/6) with morphine sul- 



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