Ointments and oleates especially in diseases of the skin / by John V. Shoemaker.

  • John Veitch Shoemaker
Date:
1890
Catalogue details

Licence: Public Domain Mark

Credit: Ointments and oleates especially in diseases of the skin / by John V. Shoemaker. Source: Wellcome Collection.

    37/338 page 19
    Twenty-one different ointment-bases were examined at a temperature of 15° C. (59° F.). One property pos¬ sessed by lanolin, particularly valuable from a pharma¬ ceutical point of view, is its ready miscibility with metallic mercury. A mixture of equal parts of lanolin and mercury may be effected in ten minutes, while after half an hour’s trituration no mercury can be perceived by the use of the lens. This fact alone renders wool-fat an important addition to pharmacy as well as medicine, the tedious and difficult manipulations formerly neces¬ sary in the preparation of mercurial ointment being now superseded. It is for this reason that the last edition of the Austrian Pharmacopoeia prescribes lanolin in the formula for mercurial ointment. Lanolin readily combines with other oils, fits, and glycerin, The only practical drawback—not a very serious one, however—is its stickiness. Mr. II. Ilelbing* has endeavored, with doubtful success, to overcome this objection by the following mixture, for which he proposes the name ungv.entum lanolini: 65 parts of anhydrous lanolin, 30 parts of liquid paraffin, and 5 parts of cerasin. Impure specimens of lanolin, containing free fatty acids, are decidedly irritant. It is desirable, therefore, to be acquainted with the tests for its purity, published by Liebreich. These are as follow: 1. A small quantity, on being heated in water over a water-bath, must show the absence of glycerin. 2. If a solution of caustic soda be added, ammonia must not be developed. 3. If a small amount be heated with water on a water-batli, the fat must separate in oily drops without producing an emulsion. 4. With litmus-paper the reaction must not be acid. 5. When well mixed with water upon a ground- *Tlie Pharmaceutical Journal and Transactions, December 21, 188'J.
    digitised image 1
    digitised image 2
    digitised image 3