Besides the liquid a goodly number of solid preparations, chiefly tablets, containing pepsin and pancreatin are offered to the profession. Among these are tablets consisting simply of pepsin and pancreatin. Since pepsin and pancreatin interact only when in solution, it is quite possible to prepare tablets which contain these ferments. The use of such tablets is, however, unscientific, since one or the other of the ferments is destroyed when it comes in contact with the fluids of the digestive tract. In addition to simple tablets containing pepsin and pancreatin only there is at present a host of “digestive tablets” on the market. Among these are some which must be classed with the “digestive impossibilities” (Reports of the Council on Pharmacy and Chemistry, 1910, Vol. 1, p. 41). The preparations referred to are tablets claimed to contain pepsin, pancreatin, diastase, hydrochloric acid and lactic acid. When it is considered that the United States Pharmacopeia defines hydrochloric acid as “a liquid composed of 31.9 per cent. by weight of absolute hydrochloric acid (HCl = 36.16) and 68.1 per cent. of water,” i. e., a solution of hydrogen chlorid, a gas, in water, it would at first appear that the incorporation of any appreciable quantity of hydrochloric acid in tablets would be impracticable. Hydrochloric acid, however, possesses to a limited extent the property of combining loosely with protein substances so that it becomes possible to bring about its combination with pepsin and similar substances to form compounds which are relatively stable at ordinary temperatures. Because of the volatility of the free acid and its limited combining power with protein substances (100 gm. boiled beef combine with 2 gm. absolute hydrochloric acid[92]), the quantity of acid in any tablet can never be large, much less than sufficient to be of any therapeutic value.
A number of firms offer “digestive tablets” for sale having formulas of which the following may be considered typical:
| Sacch. Pepsin | 4 | grains |
| Pure Pancreatin | 1 | grain |
| Diastase | 1⁄4 | grain |
| Aromatic Powder | 1⁄4 | grain |
| Lactic Acid | 1⁄8 | grain |
| Hydrochloric acid | 1⁄8 | grain |
Some manufacturers use United States Pharmacopeia pepsin in place of the saccharated article; others do not give the exact quantities of hydrochloric acid which their product is supposed to contain, but make use of the indefinite expression “q. s.;” still others state merely that hydrochloric acid is present, but make no claim whatever concerning the quantity.
From purely theoretical considerations it is possible that the tablets referred to might contain appreciable amounts of hydrochloric acid. Since the formulas for some of the tablets furnish no information concerning the content of hydrochloric acid, it seemed worth while to determine the quantity, if any, actually present in some of the tablets on the market. Accordingly a trade package of “digestive aromatic tablets,” as put up under the label of each of six American manufacturers, was purchased and submitted to examination in the Association laboratory.
Qualitative tests made on specimens from each brand of tablets demonstrated the absence of uncombined hydrochloric acid in each. Further tests[93] showed that hydrochloric acid in protein combination was present essentially in the amounts claimed in three of the specimens. In two of the others hydrochloric acid was entirely absent; in the remaining one only the merest traces of hydrochloric acid could be found.
| H. K. Mulford Company | ||
| “DIGESTIVE AROMATIC” | ||
“Pepsin, Sacch. | 4 | grains |
“Pancreatin | 1⁄2 | grain |
“Diastase | 1⁄16 | grain |
“Acid Lactic | 1⁄8 | grain |
“Acid Hydrochloric | 1⁄8 | grain |
“Aromatic Powder | 1⁄4 | grain |
| “Dose: 1 or 2 tablets.” | ||
In the above formula each tablet is said to contain 1⁄8 grain hydrochloric acid. This amount is equivalent to 0.002584 gm. (1⁄25 grain) absolute hydrochloric acid. Analysis demonstrated that each tablet contains about 0.00267 gm. hydrochloric acid (absolute HCl) or essentially the amount claimed. The average dose of diluted hydrochloric acid United States Pharmacopeia is 1 c.c., equivalent to 0.1049 gm. absolute hydrochloric acid. To obtain this quantity from the above preparation the patient would be required to swallow more than three dozen of the tablets.