This section is from the book "Materia Medica And Therapeutics Inorganic Substances", by Charles D. F. Phillips. Also available from Amazon: Materia medica and therapeutics.
There can be no doubt that the large doses - 12 to 30 gr - formerly given to patients with mental disease, and especially to those suffering from acute or violent mania, served the purpose of quieting their violence for a time, but the general results were rather injurious (Greisinger), and professional opinion is justly opposed to producing temporary quiet by this means (Bucknill). A smaller quantity, however - 1/2 to 1 gr., thrice daily - I have often known to be well tolerated by men who are in fair bodily health, and it certainly acts better when nausea and depression are not induced. The same observation has been made by Schroeder van der Kolk, a deservedly high authority: he has seen marked benefit from the remedy, and recommends it in pill after meals (to avoid vomiting), the dose to be cautiously increased from 1/4 gr.
In Puerperal Mania the last-named physician has also found small repeated doses very useful, and Dr. E. Kennedy recommends them especially for phlegmatic patients (American Journal, v. 17). Dr. Madden has seen doses of 1/8 gr. every four hours act very favorably, subduing delirium in a comparatively short time; sometimes he has used doses of 1 gr., which quieted excitement still more quickly, but were liable to depress the heart-action unduly (Medico - Chirurgical Review, ii., 1871).