The belladonna treatment is described  by Bill Pittman:

AA The Way It Began

 ISBN 0-934125-08-2, available from Hazelden books.

"Upon Wilson's arrival at Towns Hospital, he was placed in a bed and the Towns-Lambert Treatment was begun. Dr. Lambert described the belladonna treatment as follows:

Briefly stated, it consists in the hourly dosage of a mixture of belladonna, hyoscyamus and xanthoxylum. The mixture is given every hour, day and night, for about fifty hours. There is also given about every twelve hours a vigorous catharsis of C.C. pills and blue mass. At the end of the treatment, when it is evident that there are abundant bilious stools, castor oil is given to clean out thoroughly the intestinal tract. If you leave any of the ingredients out, the reaction of the cessation of desire is not as clear cut as when the three are mixed together. The amount necessary to give is judged by the physiologic action of the belladonna it contains. When the face becomes flushed, the throat dry, and the pupils of the eyes dilated, you must cut down your mixture or cease giving it altogether until these symptoms pass. You must, however, push this mixture until these symptoms appear, or you will not obtain a clear cut cessation of the desire for the narcotic...(17, p. 2126; 209,p.186)

The exact contents of each ingredient is outlined below: