This section is from the book "Dental Medicine. A Manual Of Dental Materia Medica And Therapeutics", by Ferdinand J. S. Gorgas. Also available from Amazon: Dental Medicine.
Iodine is a non-metallic, metalloid element, obtained principally from kelp (made by burning seaweed, and in the form of impure soda), which is subjected to distillation in iron retorts, after which it is mixed with sulphuric acid and black oxide of manganese. It is evolved in the form of vapor, which is condensed. The vapor is readily recognized by its beautiful violet color. Iodine is usually in the form of bluish-black crystalline scales, with a metallic lustre, a strong, peculiar odor and a hot, acrid taste. It is slightly soluble in water, and soluble in alcohol, ether, solution of chloride of sodium and a solution of iodide of potassium.
Iodine in small doses is alterative, stimulant and tonic, and acts locally as an irritant, causing redness, itching and desquamation ; exhaled in the form of vapor, it excites cough and warmth in the air passages. Taken internally it excites a sensation of heat or burning in the stomach, and in large doses is an irritant poison, inflaming the mucous membrane of the stomach and causing superficial eschars. The internal use of the iodides gives rise to an eruption of acne, especially on the face, thighs and shoulders; they have also anaphro-disiac powers when long continued. The influence of the iodides in producing iodism may be prevented by large drafts of water being used during their administration.
The odor of iodine can be detected in the blood, brain and muscles.
When combined with potassium its local irritant effect is diminished; hence the preparation known as Iodide of Potassium, Potassii Iodidum (obtained by treating an aqueous solution of potassa with iodine), is employed whenever the constitutional effects of iodine are desired, as the iodide of potassium possesses many advantages over iodine for internal use, such as being less irritant, and for this reason may be administered in larger doses and for a greater length of time; it is also more soluble than iodine alone, and when taken into the stomach is absorbed much more rapidly. The formula is Ki, and it is in the form of white crystals, of an acrid, saline taste. Some persons are peculiarly susceptible to the influence of iodine, even small doses causing unpleasant effects, such as headache, vertigo, derangement of the digestive organs, etc.
Iodide of potassium, like iodine, produces a very decided effect on the secretions, increasing them, and occasionally to the degree of ptyalism. The antidote for poisoning by iodine is starch.
Iodine and its preparations are valuable resolvents in the treatment of glandular enlargements, indurations, tumors, thickening of membranes, etc., etc.; also in scrofula, scrofulous ophthalmia, tubercular meningitis, advanced stage of pleurisy, chronic affections of the liver, etc., etc.
Iodide of potassium is much employed in mercurial poisoning and in syphilis, especially in the secondary and tertiary forms, and after the employment of mercury has proved useful; also in affections of the nervous system of a syphilitic origin, together with the other affections already referred to as indicating iodine. Externally iodine is used in the form of tincture in the treatment of enlarged scrofulous glands, cutaneous affections, erysipelas, rheumatism, gout, phlegmons, syphilitic gummatae and nodes, phagedenic ulcerations, carbuncles, diseases of the joints, wounds and parts poisoned; and as a counter-irritant in pneumonia, phthisis and pleurisy; and as injections in hydrocele and bron-chocele. The vapor is inhaled with benefit in chronic bronchitis and phthisis. Iodine also ranks highly as a disinfectant.
Of iodine alone, gr. 1/4 to gr. j two or three times a day, in the form of a pill, directly after eating on account of its irritant effect; the best form of administration, however, is iodide of potassium. Dose of the iodide of potassium, gr. iij to gr. x. A new way of giving iodine internally is by dissolving iodine in water with four times its weight of iodide of potassium, and mixing with glucose.
Tincture of Iodine - Tinctura lodi (iodine, ; alcohol, Oj).
Dose, to Compound Tincture of Iodine - Tinctura lodi Composita (iodine, ; iodide of potassium, ; alcohol, Oj).
A new tincture of iodine has been introduced by Prof. Elsberg, which may be substituted for the officinal tincture, and which can be combined with tincture of aconite root.
It is claimed that it is much stronger than the officinal 7 per cent, as it contains 20 per cent. of iodine; and that no poisonous effects have resulted from its use; one application being as beneficial as four of the officinal tincture. The formula is iodine 20.0 ; alcohol, ether, aa 40.00.
Iodine is bleached by carbolic acid, and the colorless carbolate combines all the advantages of both base and acid. One of the easiest methods to decolorize iodine is to add forty minims of a saturated solution of hyposulphite of soda to each fluid ounce of the tincture of iodine. Forty minims of the saturated solution contain about thirty-two grains of sodic hyposulphite. Another method of decolorizing iodine is to put into an open vessel a drachm of the tincture of iodine and six ounces of hot water; add twelve grains of phenol, and stir with a glass rod, when the solution will be at once bleached.
In dental practice iodine and its preparations are valuable agents, the official and compound tinctures being employed in the treatment of periodontitis, alveolar abscess, mercurial stomatitis and other forms of stomatitis, inflammation and ulceration of the gums, fungous growths of gum and tooth pulps, necrosed teeth and suppurating pulps of teeth, diseases of the antrum, caries of maxillary bones, dentigerous cysts, recession of gums and absorption of alveolar processes. The combination of equal parts of tincture of iodine, tincture of aconite, tincture of canabis indica and compound tincture of benzoin to be locally applied, is a more effectual remedy than the former aconite and iodine mixture, for periodontitis, pulpitis, inflammation about erupting third molars, and incipient alveolar pyorrhoea. It is a counter-irritant and will often abort a forming abscess.