Tincture of Nux Vomica.
By J. B. MOORE.
The tough and corneous character of nux vomica, and the obstacle this offers to the solution of its active constituents, render it one of the most difficult substances in the Materia Medica to exhaust with a limited quantity of menstruum. It is, therefore, important that the greatest care be exercised in the preparation of the tincture and all the pharmaceutical preparations of the drug.
The U. S. Pharmacopoeia directs fine powder, No. 60, to be employed in making the tincture, and gives the following directions for its preparation:—"Mix the powder with a pint of alcohol, and digest for twenty-four hours, in a close vessel, with a gentle heat; then transfer the mixture to a cylindrical percolator, and gradually pour alcohol upon it until two pints of tincture are obtained."
Having, in common with many of my brethren in the profession, had frequent difficulty in thoroughly exhausting the drug and obtaining a satisfactory preparation when complying with the above directions, I was induced about two years ago to institute a series of experiments, with the view of so amending the officinal formula and process that a more uniform and reliable tincture might be made, and, after many experiments with various modes of manipulation, and with powders of different degrees of fineness, I became convinced that a finer powder than is directed in the officinal formula was necessary to insure the perfect exhaustion of the drug, and that some change in the process was also required. As the result of my efforts, I offer the following modification of the officinal process as affording the most satisfactory results:
|Pulv. Nux Vomica, No. 80,
|a sufficient quantity.
Mix the powder with one and a half pints of alcohol, and digest for twenty-four hours, in a close vessel, at a temperature of 120°, with occasional agitation; then strain through muslin with strong expression, and rub the residue through a No. 20 sieve; then pack it firmly in a glass cylindrical percolator, and gradually pour upon it the expressed liquid, and when it has all been absorbed, continue the percolation with alcohol until two pints of tincture are obtained.
Instead of digesting the drug with only a pint of alcohol, as directed by the Pharmacopoeia, I use a pint and a half, as it is desirable to secure the solvent action of as much of the menstruum as is possible during the digestion.
I also direct the mixture to be expressed at the completion of the digestion, as the residue can then be properly packed for percolation. This is of paramount importance to the success of the operation, and is much better than pouring the mixture into the percolator and allowing it to settle and adjust itself, as in the officinal formula, because in doing so the homogeneous condition of the mass is disturbed by the partial separation of the finer and coarser particles.
The residuum should be packed so firmly in the percolator that, when percolation commences, the tincture will not pass at a faster rate than from five to eight drops per minute.
If the above directions are carefully complied with a good and reliable preparation will result. When the process is completed, the dregs in the percolator will be found to be tasteless or nearly so.
The almost insuperable difficulties attending the reduction of nux vomica to a very fine powder, with the facilities afforded by any ordinary retail drug store, forbid the idea of any pharmacist attempting to powder the drug for himself, consequently, nearly all are compelled to rely upon the wholesale market for their supply; therefore, I think that our wholesale druggists should keep constantly on hand nux vomica in very fine powder. I presume it is quite a difficult matter to reduce it to so fine a state of division, even by the aid of the appliances of the best arranged drug powdering establishments, yet, by proper treatment, it can be done.
At the time I was engaged with my experiments I found it impossible to obtain any powdered nux vomica in this market that even came up to the requirements of the Pharmacopoeia, and to procure the very fine (No. 80) powder I desired, I was obliged to send to Dr. Squibb, in Brooklyn.
There was but one or two of our wholesale drug houses that had any powder finer than from No. 30 to No. 40. Now, as pharmacists have to depend almost exclusively upon the commercial powder to prepare their tincture from, this would seem to indicate that it is nearly all made from powder entirely too coarse, and must necessarily often be of very deficient strength. To this cause may be attributed the frequent failure of physicians in deriving the desired therapeutic effects from the administration of the tincture. It is not uncommon to hear medical men remark that they have lost confidence in the virtues of tincture of nux vomica, and many have ceased to employ it in their practice. But I believe that if it be carefully and properly prepared it is as efficient and reliable a preparation of the drug as any that is made.
Phila., Pa., Feb., 1871.