Ash.—When heated, all the specimens were found to yield practically no ash, the residues from 1 gm. samples weighing in no case more than 0.0004 gm.
Absence of Paraphenetidin.—When tested by the methods of the United States, British, German and French pharmacopeias, the absence of an impurity of paraphenetidin was shown in all specimens, with the exception of one specimen obtained from Powers-Weightman-Rosengarten Co., which gave a positive, though not strong, reaction and two other specimens of the same firm which reacted still more faintly.
TABLE SHOWING RESULTS OF ANALYSES OF VARIOUS SPECIMENS OF ACETPHENETIDIN AND PHENACETIN*
| Name | Physical Appearance | Melting Point (Corr.) C. | Water-Soluble Matter in, per Cent. | Ash, per Cent. | Para- phenetidin, U. S. P. Test† | Para- phenetidin, Swiss Test† |
| Acetphenetidin (Farbenfabriken) (1) | Very fine homogeneous crystalline powder | 134.2 | 0.17 | 0.02 | – | + |
| Phenacetin (Farbenfabriken) | Very fine homogeneous crystalline powder | 133.7 | 0.06 | 0.00 | – | + |
| Phenacetin (Lehn & Fink) | Fine crystalline powder, not uniform | 134.7 | 0.11 | 0.02 | – | + |
| Acetphenetidin (Lehn & Fink) | Fine crystalline powder, not uniform | 134.8 | 0.13 | 0.00 | – | + |
| Acetphenetidin (P. W. R.) (1) | Homogeneous crystalline powder | 134.3 | 0.19 | 0.03 | + | + |
| Acetphenetidin (P. W. R.) (2) | Homogeneous crystalline powder | 134.7 | 0.16 | 0.02 | + | + |
| Acetphenetidin (P. W. R.) (3) | Homogeneous crystalline powder | 134.7 | 0.14 | 0.02 | + | + |
| Acetphenetidin (P. W. R.) (4) | Fine crystalline powder | 133.6 | 0.20 | 0.01 | – | – |
| Acetphenetidin (Squibb) | Fine crystalline powder | 134.3 | 0.19 | 0.00 | – | + |
| Acetphenetidin (Merck) | Fine crystalline powder | 134.8 | 0.15 | 0.03 | – | – |
| Acetphenetidin (Mallinckrodt) | Fine crystalline powder | 134.2 | 0.11 | 0.01 | – | – |
| * In all cases identity was confirmed; acetanilid was absent; carbonizable matter was absent. | ||||||
| † In this column plus indicates presence; minus, absence. | ||||||
While this firm’s product alone gave any reaction whatever when the U. S. P. test for paraphenetidin was applied with the test of the Swiss pharmacopeia, all but Acetphenetidin (Mallinckrodt), Acetphenetidin (Merck) and one specimen of Powers-Weightman-Rosengarten Co. gave positive, though very faint, reactions, indicating that the majority of specimens, including those of the original manufacturer, contain a minute trace of this impurity.
Our findings regarding the product of Powers-Weightman-Rosengarten Co. having been communicated to this firm, their correctness was acknowledged. At the same time the firm wrote: “All that we have on hand now gives negative tests for paraphenetidin, and we believe our present records are correct when we state that all lots which we are supplying now, and have been supplying for some time past, answer all U. S. P. requirements.”
This examination appears to demonstrate that the chemical substance, para-acetphenetidin, whether sold as acetphenetidin, U. S. P., or as phenacetin, is practically identical. The impurity of the product of some of the specimens coming from Powers-Weightman-Rosengarten Co. is too slight to be considered dangerous. Furthermore, a comparison of the “lot numbers” indicates that this firm has been improving its product steadily so that in the future its assurances of an unimpeachable product may be relied on. Inasmuch, therefore, as acetphenetidin complies with all the pharmacopeial requirements as to identity and purity, in just the same way as phenacetin, which sells for as high as five times the price of acetphenetidin, physicians need not hesitate in using the title of the U. S. P. “acetphenetidin” when prescribing this produce.—(From The Journal A. M. A., March 16, 1912.)
Acetphenetidin and Phenacetin
A physician-pharmacist writes: “If a prescription calls for ‘phenacetin,’ should the pharmacist dispense ‘phenacetin-Bayer’—that is, the phenacetin manufactured by the original patentee—or would he be justified in dispensing the official acetphenetidin, manufactured by any reliable chemical or pharmaceutical house?”
Unless the pharmacist happens to know that the physician in writing the prescription desired the Bayer brand, he would be justified in dispensing acetphenetidin, U. S. P. As a general thing, physicians use the word “phenacetin” without intending to prescribe any particular brand or make, simply because they are familiar with this word and are not familiar with the official term “acetphenetidin.” They will doubtless continue to use the term “phenacetin” and we know of no sufficient reason for doing otherwise. During the life of the patent the word “phenacetin” became a familiar one, and the product became generally known by this term. But a coined name for a patented article loses its proprietary character and becomes the common name of the article when the patent expires. In other words, when the patent expires, not only the product but also the name itself becomes common property. This principle has been recognized by the courts. Those who formerly controlled the product and the name “phenacetin” evidently recognized this principle, for they have taken no steps to prosecute a firm in this country which sells the product openly under the name “phenacetin.” It might be added that the preparation is official in most foreign pharmacopeias under the name “phenacetin.” In agreement also with this principle the Council on Pharmacy and Chemistry (The Journal, April 27, p. 1298) lists in New and Nonofficial Remedies such products as “lanolin,” “phenacetin,” “sulphonal” and “trional” as non-proprietary names applied to Adeps lanæ hydrosus, U. S. P., Acetphenetidinum, U. S. P., Sulphonmethanum, U. S. P., and Sulphonethylmethanum, U. S. P., respectively.