Thymol. Thymol, CHO, U.S.P.

Thymus vulgaris, Linne'.  A phenol occurring in the volatile oil of this and other plants.

Habitat.  S. Europe (Portugal to Greece); cultivated in gardens, etc.

Syn.  Common Garden Thyme, Mother of Thyme; Acidum Thymicum Thymic Acid,  Methyl-propl phenol; Fr. Acide Thymique; Ger. Herba Thymi, Thymian; Thymolum,  Thymiansaure.

Thy'mus.  L. fr. Gr...., strength, its invigorating smell.  Used in temples as incense.

Vul-ga'ris.  L. ordinary, common -- i.e., the kind growing wild and in common use.

Plant

Small shrub, 25-30 Cm. (10-12') high; stem and branches quadrangular; bark pale brown, shoots purplish; stems .5 Mm. (1/50') thick, grayish-brown, pubescent, nodes 5-20 Mm. (1/5-4/5') apart.  Thymus, Thyme, N.F.  Leaves and flowering tops with not more than 3 p.c. of stems over 1 Mm. (1/25') thick, or other foreign organic matter, yielding not more than 4 p.c. of acid-insoluble ash.  Leaves linearlanceolate, ovate, .5-6 Mm. (1/50-1/4') long, .5-2 Mm. (1/50-1/12') broad, acute base tapering into short petiole, revolute, grayish-green, puberulent, many non-glandular hairs, grayish, pubescent beneath; numerous glandular secreting hairs above, depressed in cuticle giving glandular-punctate appearance; flowers polygamous, bilabiate, small, pubescent, upper lip 3-toothed, lower 2-toothed, purplish; fruit nutlets, .5 Mm. (1/50') broad, spheroidal.  Powder, light-green -- non-glandular hairs 2 types, glandular hairs 2 types, leaf chlorenchyma with vascular tissue and epidermal cells, stomata, pollen grains.

Constituents

Volatile oil 2.5 p.c. (Thymol), resin, tannin, gum, ash 14 p.c.

Oleum Thymi. Oil of Thyme, N.F. -- A volatile oil distilled from the flowering plant containing not less than 20 p.c., by volume of phenols.  It is a colorless or red liquid, characteristic odor and taste, soluble in 2 vols. 80 p.c. alcohol, sp. gr. 0.912, levorotatory; contains at least 20 p.c., by volume, of phenols, also cymene, C10H14 l-pinene, borneol, linalool; the phenol content in the French and German oil, amounting to 25-42 p.c., is mostly thymol, but sometimes carvacrol, or a mixture of the two, whereas in the Spanish oil it is chiefly carvacrol, amounting to 50-70 p.c.  Adulterations: Oil of turpentine which lowers specific gravity and increases angle of rotation, while wild thyme oil only does the latter.  Test: 1. Shake 1 cc. with hot distilled water 10 cc., cool, pass aqueous layer through a wetted filter -- filtrate not blue or violet with a drop of ferric chloride T.S.  Should be kept cool, dark, in well-stoppered, amber-colored bottles.  Dose, mj-5 (.06-.3 cc.).

Thymol. Thymol U.S.P. -- This monatomic phenol, occurring in the volatile oils of Thymus vulgaris, Monarda punctata, and Ptycho'tis Cop'tica (Ajowan -- Umbelliferae), the latter alone supplying most of the commercial article, is obtained by subjecting to freezing the residue left upon distilling any of these oils below 200 degrees C. (392 degrees F.), whereby thymol crystallizes out; or may agitate this residue with sodium hydroxide solution, and after a time add hot water to separate sodium thymol (NaCHO) solution from thymene, and to allow unattacked oil to float on top; to sodium hydroxide solution add hydrochloric acid which sets thymol free as an oily layer and upon cooling crystallizes when a crystal of thymol is added; yield 20-61 p.c.  It is in large colorless, translucent, rhombic prisms, aromatic, thyme-like odor, pungent, aromatic taste, very slight caustic effect upon the lips; soluble in glacial acetic acid, fixed or volatile oils, water (1000), alcohol (1), chloroform (.7), ether (1.5); olive oil (1.7); alcoholic solution (1 in 20) neutral, optically inactive; isomeric with carvone (carvol, carvacrol); as a solid heavier than water, when liquefied by fusion lighter than water, melts at 50 degrees C. (122 degrees F.); liquefies when triturated with equal weight of ears, thready pulse, low temperature--treat symptoms, withdraw drug.  OIL: Chlorosis, rheumatism, neuralgia, bronchitis, diarrhea, gleet, gonorrhea, leucorrhea, vesical catarrh; externally in baths, lotions for scabies, muscular rheumatism, to correct fetor from sores, ulcers, gangrene.  Applied to cotton for toothache, earache, for veterinary practice, scenting soap.

Thymacetin, CH.CHOCHCHNH.COCH, a derivative, has the same relation to thymol that phenacetin has to phenol, and is prepared similarly; it is a white crysstalline powder, soluble in alcohol, slightly in water.  Analgesic, hypnotic, antiseptic; used in neuralgic headache like phenacetin.  Dose, gr. 5-15 (.3-1 Gm.).

Thyme plant (fresh) is used as a condiment to aid digestion of fat pork, goose, duck, etc., and to flavor insipid dishes, as is sage, marjoram, parsley; it is used also with other aromatic herbs in baths, cataplasms, fomentations, for rheumatism, gout, scabies, indolent ulcers.