Vaginal and Urethral Injections do not differ greatly from lotions, except that they are sometimes weaker in active ingredient, owing to larger quantities being used in irrigating. The following are the amounts of the more common medicaments used in this way for each ounce of distilled water:

Hypodermic Injections are in most cases plain solutions of alkaloidal or other salts in distilled water, and the principal point to observe in preparing them is that all the utensils used should be sterilised by thorough washing and drying in an oven at a temperature of 2200 F. The distilled water must also be recently sterilised by boiling. If these precautions are taken, and the bottles to contain the finished solutions are also sterilised, the solutions keep for a long time, if excluded from the air. Camphor, saccharin, salicylic acid, and chloroform are amongst the best non-irritant preservatives of hypodermic injections- salicylic acid being the best of all, in the proportion of 1/2 grain to the ounce. Boric acid is useless. The practice is growing amongst medical men of having the active ingredients for hypodermic injections in the shape of lamels, tabloids, tabellae, and other compressed or dry forms, as they keep indefinitely, and an injection may be prepared from one of them placed in the barrel of the syringe. Experience has pointed to the conclusion that when sores have resulted from hypodermic injections, these have been occasioned by some micro-organisms in the solution. Glycerin, if it form an ingredient in the injection, should be the purest procurable.

Clear solutions may often require filtration, but it is important that the filters should be thoroughly cleansed by passing a quantity of distilled water through them. We subjoin the hypodermic doses most frequently prescribed:

Dispensers will note that there are official (B.P.) formulae for apomorphine, cocaine, ergotin, and morphine hypodermic injections. Sterilised water is used in each case.