This section is from the book "A Practitioner's Handbook Of Materia Medica And Therapeutics", by Thos. S. Blair. Also available from Amazon: A Practitioner's handbook of Materia Medica and Therapeutics.
Agaricus Muscarius, Fly Agaric, a poisonous fungus. This substance in attenuation is employed by some homeopathic physicians in various forms of cerebral excitement and the delirium of fevers (I I of the IX or 2X), but it has no established place in therapeutics and is dangerously toxic. So far as known, its action largely depends upon the contained muscarine. Merck's muscarine nitrate, made up in alcoholic solution and employed in doses representing 1-30 to 1-15 grain of the nitrate, is useful in night sweats and diabetes insipidus and to oppose the action of atropine, but the tincture of the fungus would better not be used in therapeutics. Agaricin represents it and can be employed in doses of .xl to I grain, but is uncertain in action.