Pepsinum

Scale pepsin is not so suitable for pills as the partly insoluble powder. Make a rather soft mass with a mixture of equal parts of glycerin, syrup, and water, and roll quickly. Five grains of pepsin and acid, hydrochlor. dil. mj. make a very good mass. Some combinations give trouble, e.g.:

No. I. needs no excipient, as the quinine sulphate and carbolic acid liquefy and mass the pepsin. Mix the sulphate and pepsin in the mortar, add the carbolic acid, mass, and roll quickly. To No. II. add 3 grains of powdered tragacanth and mass with glycerin and water (equal parts). Pancreatin masses well with glucose syrup.

Phosphorus

When this is ordered in prescription the simplest method is to dissolve the phosphorus in carbon bisulphide and pour upon a suitable powder, as in the following:

Solve et adde-

Ut fiat massa gr. c. To be divided into pills of the strength required, and varnished or coated in the ordinary way.

This mass is of good consistence, easily manipulated, and readily soluble. A drop of oil of cloves added to the carbon bisulphide lessens its tendency to inflame. This method is the most expeditious for the dispensing-counter. Another good plan is to rub up some liquorice powder (1/2 to 1 grain for each pill) with half its weight of water, pour on it the bisulphide solution, stir well and without pressure, and make into a mass with compound tragacanth powder. The water effectually prevents oxidation of the phosphorus, and the bisulphide is dissipated in massing. The method also serves for the following:

If one has to make, say, 33 pills, rub the quinine and extract together with 15 grains of powdered liquorice and 5 drops of water. Now dissolve the phosphorus in 5 or 6 drops of bisulphide of carbon in a small test-tube; mix with the other ingredients, and mass quickly with glycerin of tragacanth. The British Pharmacopoeia phosphorus pill-mass is fatty, because it is considered that fat preserves the phosphorus from oxidation. The mass is made by dissolving 1 gramme of phosphorus and 20 grammes of theobroma oil in 20 c.c. of carbon bisulphide, evaporating off the bisulphide, then adding 20 grammes of theobroma oil, 11 grammes of wool-fat, 16 grammes of kaolin, and 32 grammes of sodium sulphate. This is an improvement on the 1898 form, disintegration in the stomach being ensured by the kaolin and sodium sulphate. Each grain of the mass contains 1/100 grain of phosphorus. Phosphorus pills should always be varnished or coated with a solution of wax in ether (1 in 16), and finished off with French chalk.

Pil. Coloc. Co. as now made with resin of scammony invariably flattens. This is prevented to some extent by adding from 10 to 20 drops of potash solution or aromatic spirit of ammonia to the ounce of mass, or by substituting soap for the sulphate of potash. The addition of a fibrous powder such as liquorice gives durability to the mass. An excellent mass is made by adding 10 grains of powdered tragacanth to 180 grains of the species and massing with 15 minims of water. Pills made in this manner take a fine polish and retain their shape well.

Pil. Hydrargyri. - When this is prescribed with a soft extract the latter should, if possible, be dried or used in powder.

Pil. Hydrarg. Subchlor. Co., B.P. 1898, with pill-masses having an aqueous excipient, invariably formed a crumbly combination. The B.P. 1914 has remedied this by omitting the castor oil and replacing it with glucose syrup, with a little acacia and tragacanth, as suggested by Sir James Sawyer, M.D.