Improved Method of Exhausting Drugs.
By ALFRED B. TAYLOR.
For some years past I have employed a process for making some of the fluid extracts, tinctures, etc., of the Pharmacopoeia, which has proved very satisfactory. The plan has probably occurred to others, but I have never seen it published, nor have I ever heard it suggested by any one, and I have thought a notice of it might be acceptable to the readers of the Journal.
I have found it especially serviceable in making those preparations which are made from drugs that are difficult to exhaust with small quantities of menstruum.
The process consists in using a portion of the finished preparation (from a previous operation) to macerate and partially exhaust the drug before using the new portion of menstruum, and as there is no limit to the quantity of finished preparation that can be used where necessary, it is possible to exhaust completely the drug operated on.
For example, let it be required to make two pints of tincture of arnica flowers.
|Arnica flowers, in No. 20 powder,
|6 oz. av.
|Tincture of arnica flowers
|Diluted alcohol, a sufficient quantity to make
Moisten the powder with a pint of the tincture of arnica flowers, and macerate for twenty-four hours; then pack it firmly in a cylindrical percolator, and gradually pour upon it, first the remainder of the tincture of arnica flowers, and afterward diluted alcohol, until four pints of tincture are obtained.
I have used this process with great advantage in making the fluid extract and the tinctures of cinchona.