The alkaloid obtained from the leaves of Duboisia myoporoides, Robert Brown (Nat. Ord. Myoporaceae), the Corkwood elm or Ngmoo of Australia and New Caledonia. Dose, 1/100 to 1/50 grain.
Preparations.—1. Duboisinae Sulphas, Duboisine Sulphate. Dose, 1/100 to 1/50 grain.
2. Duboisina Hydrochloridum, Duboisine Hydrochloride. Dose, 1/100 to 1/50 grain.
Action and Therapy.—External. The sulphate of this alkaloid is sometimes used as a substitute for atropine as a mydriatic. Like atropine, it is contraindicated by glaucoma and diseases of the fundus of the eye on account of its power to increase intraocular tension. It is a more rapid mydriatic and paralyzes accommodation more quickly than atropine and is less irritant to the conjunctivae.
Internal. Duboisine is very similar to, if not identical with, hyoscyamine, and the physiological effects of it are practically the same as those of the alkaloids of belladonna, hyoscyamus and stramonium. Sulphate of duboisine is an effective antagonist of muscarine and has been successfully employed in poisoning by mushrooms. It also checks colliquative sweating. It is reported prompter in action than atropine, and is said to be a better calmative and hypnotic in states of mental excitement. The morphine habit, paralysis agitans, and especially the excitability and insomnia of the insane have been treated with it. Administered in the smaller doses twice a day it is said to produce quiet, refreshing sleep. It frequently causes gastric disturbances, especially vomiting without previous nausea, and undoubtedly decreases the secretion of urine, hence it should be used with care and judgment.