Linimentum Ammoniae (U. S. P.)—Ammonia Liniment.
SYNONYMS: Volatile liniment, Common liniment.
Preparation.—"Ammonia water, three hundred and fifty cubic centimeters (350 Cc.) [11 fl℥, 401♏]; alcohol, fifty cubic centimeters (50 Cc.) [1 fl℥, 332♏]; cotton seed oil, six hundred cubic centimeters (600 Cc.) [20 fl℥, 138♏]. To make one thousand cubic centimeters (1000 Cc.) [33 fl℥, 391♏]. Mix them by agitation in a bottle, which should be well stoppered. This liniment should be freshly prepared when wanted"—(U. S. P.).
Or, take of solution of ammonia, 1 fluid ounce; olive oil, 2 fluid ounces. Mix and agitate them well together (Ed.—Lond.). The British Pharmacopoeia (1898) formula differs from the latter in adding 1 fluid ounce of almond oil. In this liniment a soap is formed by the union of the oil and ammonia, which is but imperfectly dissolved, and a white oleo-compound of ammonium is formed with some glycerin.
The U. S. P. formula gives a liniment fluid at ordinary temperature, and differs from that of 1870 in the substitution of cotton seed oil for olive oil. This liniment is liable to separate into two parts. The alcohol is designed to retard this separation. It has been suggested by Prof. Maisch that if 1/6 portion of olive oil be substituted for a like amount of cotton seed oil, a better liniment would result. Lard oil is said to form quite a uniform mixture. By substituting camphor liniment for the olive oil Camphorated volatile liniment (Linimentum Ammoniae Camphoratum) may be formed.
Action and Medical Uses.—This preparation is used as a rubefacient in rheumatic and neuralgic pains, sore throat, pleurisy, sprains, bruises, etc. It may be applied over the part on flannel, or the skin may be gently rubbed with it. If it becomes too active, it must be weakened with a sufficient quantity of oil. It will vesicate if evaporation be prevented. Care should be exercised in applying it to children and to old people lest blistering occurs.