Benzoin and Benzoic Acid

Botanical name: 

Benzoinum, Benzoin,—is a balsamic resin obtained from Styrax Benzoin, a Siamese tree (nat. ord. Styraceae). It occurs in agglutinated tears, or a brownish mass, of little taste, but agreeable odor, soluble in alcohol and solution of potassa.; and consists of Benzoic Acid, 10 to 20 per cent., together with Resins 80 per cent., and a trace of a volatile oil. Dose, gr. x-xxx.

Acidum Benzoicum, Benzoic Acid, HC7H5O2,—occurs in light, feathery plates and needles, and is obtained from Benzoin by sublimation. Soluble in 2 of alcohol, and in 500 of water; but with Borax, 1 part of each are soluble in 100 of water. Dose, gr. x-xxv, in wafers.

Preparations,—including the salts of Benzoic Acid, or Benzoates.

Adeps Benzoinatus, Benzoinated Lard,—bas of Benzoin 2 per cent.
Tinctura Benzoini, Tincture of Benzoin,—20 per cent. Dose, ʒss-j.
Tinctura Benzoini Composita, Compound Tincture of Benzoin, (Friar's Balsam),—has of Benzoin 12, Aloes 2, Styrax 8, Balsam of Tolu 4, and Alcohol to 100 parts. Dose, ʒss-ij, but generally used locally.
Ammonii Benzoas, Ammonium Benzoate,—soluble in 5 of water, and in 28 of alcohol. Dose, gr. v-xxx.
Lithii Benzoas, Lithium Benzoate,—soluble in 4 of water, and in 12 of alcohol. Dose, gr. v-xxx.
Sodii Benzoas, Sodium Benzoate,—soluble in about 2 of water, and in 45 of alcohol. Dose, gr. v-ʒj. Is efflorescent.

Physiological Action. The action of Benzoin is due to Benzoic Acid, which is stimulant and irritant to mucous membranes and raw surfaces, also highly antiseptic and disinfectant, a stimulating expectorant, and a diuretic. Taken internally it causes epigastric heat, increases the pulse-rate, and stimulates the action of the skin, the salivary glands, and the bronchial mucous membrane. It acidifies the urine, and increases its quantity, and is chiefly excreted by the kidneys, in part unchanged, and partly as hippuric acid after uniting with glycocoll. Benzoin acts as an irritant to the mucous membrane of the fauces and nasal passages; its powder inhaled causing sneezing and coughing.

Therapeutics. The uses of Benzoin and Benzoic Acid are chiefly local, but they may be used with benefit internally in several affections of the respiratory and urinary passages. In—

Chronic Bronchitis of the aged,—Benzoin as a stimulating expectorant.
Laryngeal and Bronchial affections,—Benzoin by steam atomization.
Chlorosis and several Uterine disorders,—Benzoin internally is of benefit.
Chaps and Sore Nipples,—the compound tincture 1, to 4 of glycerin and water.
Freckles, etc.,—either tincture with 20 of water, locally as a cosmetic.
Wounds of foul character,—the tinctures are excellent applications.
Cystitis with alkaline urine and phosphatic deposits,—Benzoic Acid or its salts are extremely valuable, being the only certain means of neutralizing morbid alkalinity of the urine.
Phosphatic Calculi,—a long course of the Ammonium Benzoate.
Gout and Uric Acid Diathesis,—the Lithium Benzoate is very efficient.
Diphtheria, Scarlet Fever, and other septic diseases,—the Sodium Benzoate is largely used instead of the salicylates, as an internal antiseptic and antipyretic, and has rendered good service.
Phthisis and Whooping-cough,—the Sodium salt by inhalation with atomizer.

A Compend of Materia Medica, Therapeutics, and Prescription Writing, 1902, by Sam'l O. L. Potter, M.D., M.R.C.P.L.