This section is from the book "A Text-Book Of Pharmacology, Therapeutics And Materia Medica", by T. Lauder Brunton. Also available from Amazon: A text-book of pharmacology, therapeutics and materia medica.
Not officinal. - An alkaloid, C3H15NO3, prepared from the Fly Agaric, Amanita muscaria, a fungus growing in all parts of the world.
Muscarine can be prepared artificially fromcholin, C5H15NO2, by oxidation with nitric acid : it differs from cholin by having one atom of oxygen more, and may be represented in a constitutional formula as N3(CH3)3 CH2. OH
CH(OH)2. Betain (trimethylglycin),
C5H13NO3, is also related to muscarine and cholin, and is said to have been produced by oxidation of the latter. Cholin and artificial muscarine have a similar action, which differs from that of natural muscarine, in paralysing the ends of motor nerves like curare. Artificial muscarine is 500 times as strong as cholin, and 50 times more lethal in its action.1 It is not completely antagonised by atropine as natural muscarine is.
Characters. - A viscid, yellowish-brown liquid, soluble in water, and giving the reactions of an alkaloid (p. 504).
Dose.- 1/2 to 3/4 grain, hypodermically.
Action. - Muscarine is a myotic (p. 219), and an antihidrotic (p. 441) and sialagogue (p. 357). It has a powerful action on the heart, paralysing the cardiac muscle (p. 316) and stimulating the inhibitory ganglia (p. 317). It is a general emetic (p. 373), and diminishes the activity of the respiratory centre (p. 241). Its action is completely neutralised by atropine (p. 495).
Uses. - Hypodermically, muscarine has been used in checking night-sweats.