Guaiacol

Guaiacol, Guajacolum (Ph VII), monomethyl ether of creosote, C₆H₄(OH). .(OCH₃) (1, 2), is the main component of creosote, from which it is obtained by repeated fractional distillation; it is sold either as colorless or pale yellow crystals melting at 28.5° (Guajacolum crystallisatum), or as a transparent oily liquid (Guajacolum absolutum) with a characteristic aromatic odor and a burning taste, specific gravity 1.117-1.143; boiling point 200-205°; it dissolves in 60 parts of water, is easily soluble in alcohol, ether, and fatty oils. G. is easily absorbed by mucous membranes and skin; 5 hours after oral administration or skin application, its presence can be detected in the urine; it is excreted in small amounts by the respiratory tract, mainly by the kidneys. G. was proposed by Sahli instead of creosote, which is inconsistent in its composition and strongly irritating locally, for tuberculosis. The mechanism of action of G. in tuberculosis cannot be considered fully elucidated; sufficient pharmacological data to consider it a specific remedy against tuberculosis are not yet available; however, numerous clinical observations have shown with sufficient convincingness that prolonged application of G. in chronic catarrhs of the respiratory tract and pulmonary tuberculosis has a beneficial influence on the patient. Guaiacol is applied: orally in doses from 0.05 to 0.5 per dose and up to 1.5-2.0 per day in gelatin capsules, in pills, in emulsions, in solutions, in cod liver oil and in milk; in the form of ointments; in the form of inhalations; a solution of iodoform in guaiacol (1:5) has been proposed for injection into tuberculous joints. Due to its local irritating properties and burning taste, G. is not always well tolerated by patients, and therefore a number of G. derivatives have been proposed, largely devoid of these unpleasant properties, such as: 1) Benzosolum, Guajacolum benzoicum - C₆H₄OCH₃.CO.C₆H₅, a white soft crystalline powder, odorless and tasteless; insoluble in water, easily soluble in hot alcohol; melting point 60-61°. In the intestine it decomposes into G. and benzoic acid. It is prescribed for tuberculosis of the lungs and intestines and for cystitis in doses from 0.2 to 0.5, three or four times a day. 2) Duotalum, G. carbonicum (Ph VII), carbonic guaiacol, CO₂(O.C₆H₄.OCH₃)₂, a white crystalline powder, odorless and tasteless, insoluble in water, easily soluble in hot alcohol. It passes through the stomach unchanged, decomposing in the intestine into G. and carbonic acid. It is well tolerated by patients. It is prescribed for tuberculosis, pneumonia, bronchial catarrh, and for diarrhea for disinfection of the intestine, 0.2-0.5 in powders, tablets, and pills, 3-4 times a day. 3) Geosotum, isovaleric acid guaiacol, C₄H₉CO.OC₆H₄OCH₃, a pale yellow, oily, slightly water-soluble liquid; soluble in alcohol, ether, and fatty oils. Boiling point 245-265°. It does not irritate the stomach. It is prescribed for tuberculosis, pneumonia, bronchitis, and as a disinfectant for the intestine, 0.2-0.5 in gelatin capsules, 3-4 times a day; when prescribed in drops, patients often complain of an unpleasant taste, nausea, and vomiting. 4) G. phosphoricum, phosphoric acid guaiacol, PO₄. .(OCH₆H₄OCH₃)₃, a white crystalline powder, insoluble in water, soluble in alcohol and chloroform. Melting point 98°. Dosage: from 0.2 to 0.5, three or four times a day. 5) G.-Salol, guaiacol-salol, C₆H₄(OH)CO.OC₆H₄OCH₃, a white crystalline powder, odorless and tasteless, insoluble in water, soluble in alcohol. Melting point 65°. It is prescribed 1.0 several times a day for disinfection of the intestine in tuberculosis. 6) Guajacylum, Calcium sulfoguajacolicum (C₆H₈)OH[(OCH₃) (SO₃)₂],Ca, a bluish-gray powder, easily soluble in water and alcohol; aqueous solutions are colored violet-red. 5-10% solutions are used as local anesthetics (subcutaneous and submucosal injections). 7) Kalium sulfoguajacolicum, guaiacol-sulfuric acid potassium, Thio- /OH colum, thiocol, C₃H₆S₂-------OCH₃, a white crystalline powder, almost odorless, slightly salty-bitter taste; soluble in 7.5 parts of water, insoluble in anhydrous alcohol, ether, and chloroform. It does not possess local irritating properties; it is easily absorbed. It is prescribed in doses from 0.5 to 1.0, 2-3 times a day, in powders, tablets, and solutions (Ph VII). 8) Sirolin, a 10% solution of thiocol in orange syrup. Dosage: 3-4 times a day by a teaspoon or tablespoon, washed down with milk. 9) Styracolum, G. cinnamylicum, cinnamic acid guaiacol, white needle-like crystals, odorless and tasteless; insoluble in water, soluble in alcohol and chloroform. Melting point 130°. In the intestine it decomposes into guaiacol and cinnamic acid, acting disinfectively and anti-gas-forming. It is often prescribed for tuberculosis in doses from 0.5 to 1.0, three or four times a day. Due to absorption through the skin, Styracolum is applied in the form of guaiacol-vasogen for rubbing in pleural adhesions, fibrous tuberculosis processes, etc.