If 200 mgrms. of thebaine are heated to boiling with 1·4 c.c. of HCl and 2·8 c.c. of water, and the solution diluted, after boiling, with 4 c.c. of water, crystals of thebaine hydrochloride form in the yellow fluid in the course of a few hours.—Flückiger.
§ 375. Effects.—There is no disagreement of opinion as to the action of thebaine. By the united testimony of all who have experimented with it, the alkaloid belongs to those poisons which produce tetanus, and the symptoms can scarcely be differentiated from strychnia. In Baxt’s experiments on frogs he showed that there was some considerable difference in details in the general course of the symptoms, according to the dose of the poison. A small dose (such, for example, as ·75 mgrm.) injected into a frog subcutaneously produces immediate excitement, the animal jumping about, and this stage lasting for about a minute; it then becomes quieter, and has from three to six minutes’ sleep; in a little time this comatose state is followed by reflex tetanic spasms and then spontaneous tetanic spasms. With three times the dose, the tetanic convulsions commence early, and death takes place in from two to six hours. Baxt[412] found 6 to 7 mgrms. kill rabbits with tetanic convulsions in from fifteen to twenty-five minutes. Crum Brown and Fraser also found that 12 mgrms. injected into rabbits were fatal; it may then be presumed that the lethal dose for a rabbit is about 5 mgrms. per kilo. A frog’s heart under the action of thebaine, and removed from the body, beats quicker and ceases earlier than one in distilled water. Thebaine has been administered to the insane subcutaneously in doses of from 12 to 40 mgrms., when a rise of temperature and an increase in the respiratory movements and in the circulation were noticed.[413]
[412] Sitzungsber. d. Wien. Akadem., lvi. pp. 2, 89, 1867; Arch. f. Anat. u. Physiol., Hft. 1, p. 112, 1869.
[413] F. W. Müller, Das Thebaine, eine Monographie, Diss., Marburg 1868.
The fatal dose for a man is not known; ·5 grm., or about 8 grains, would probably be a poisonous quantity.
§ 376. Cryptopine (C21H23NO5) was discovered by T. & H. Smith in 1867.[414] It is only contained in very minute traces in opium—something like ·003 per cent. It is a crystalline substance, the crystals being colourless, six-sided prisms, without odour, but with a bitter taste, causing an after-sensation like peppermint. The crystals melt at 217°, and congeal in a crystalline form again at 171°; at high temperatures they are decomposed with evolution of ammoniacal vapour. Cryptopine is insoluble, or almost so, in ether, water, and oil of turpentine; it is soluble in acetone, benzene, and chloroform; the latter is the best solvent, or hot alcohol; it is insoluble in aqueous ammonia and in solutions of the caustic alkaloids. Cryptopine is strongly basic, neutralising fully mineral acids. Concentrated sulphuric acid colours cryptopine pure blue, the tint gradually fading from absorption of water from the atmosphere. On a crystal of potassic nitrate being added, the colour changes into a permanent green. With ferric chloride cryptopine gives no colour—thus distinguishing it from morphine. The physiological properties of cryptopine have been investigated by Dr. Harley;[415] it has a narcotic action, about double as strong as narceine, and four times weaker than morphine. Munk and Sippell[416] found that it gave rise in animals to paralysis of the limbs, and occasionally asphyxic convulsions before death.
[414] Pharm. Journ. Trans. [2], viii. pp. 495 and 716.