Ii = 126.92.

(Syn., Iodinium; Fr. lode; Ger. Jodum, Jod.)

The element iodine (Gr. lov, violet, +

form, likeness - i. e., from its violet-colored vapor) is official, and occurs in nature combined with the metals sodium, potassium, magnesium, etc.

Manufacture: An important source is the ash (kelp) of seaweeds, which contains about 1/204 of its weight of iodine; the weeds are dried, burnt at the lowest possible temperature, ash exhausted with hot water, solution filtered, evaporated, cooled, when the less soluble salts - potassium chloride, sodium carbonate, and sulphate crystallize out; to mother-liquor, containing sodium and magnesium iodides, heated in lead retorts to 60° C. (140° F.) manganese dioxide and sulphuric acid are added, when iodine distils over, being collected in glass receivers - 2NaI + 3H2SO4 + MnO2 = I2 + 12NaHSO4 + MnSO4 + 2H2O. Much iodine is now obtained in Chile from the mother-liquor of saltpetre, containing about 22 p. c. of sodium iodate, by treating it with sulphurous acid - 2NaIO3 + 5H2SO3 = Na2SO4 + 4H2SO4 + I2; the liberated iodine is filtered or distilled off, and may be purified by mixing with potassium iodide and subliming. It is in heavy, bluish-black brittle, rhombic plates, metallic lustre, distinctive odor, sharp, acrid taste, sp. gr. 4.66, imparts deep brown, evanescent stain to the skin, slowly destroys vegetable colors; soluble in chloroform, ether, aqueous solutions of iodides, carbon disulphide (4), alcohol (12.5), glycerin (80), water (2950); solution in alcohol or aqueous solution of potassium iodide - reddish-brown color; in chloroform or carbon disulphide - violet color; contains 99.5 p. c. of iodine. Tests: 1. Volatilizes slowly at ordinary temperatures; fumes at 114° C. (237° F.), gradually dissipating in purple vapor, leaving residue .05 p. c. 2. Saturated aqueous solution + starch T. S. - blue color, discharged on boiling, but reappears upon cooling. Impurities: Chlorine, bromine, cyanogen iodide, moisture. Should be kept cool, in glass-stoppered bottles. Dose, gr. 1/4-1 (.016-.06 Gm.).

Preparations. - 1. Liquor Iodi Compositus. Compound Solution of Iodine. (Syn., Liq. Iodi Co., Lugol's Solution; Br. Tinctura Iodi Fortis, Strong Tincture of Iodine, Liniment of Iodine, Liquor Iodinii Compositus; Fr. Solute iodure de Lugol; Ger. Lugolsche Jodlosung.)

Manufacture: 5 p. c. Dissolve iodine 5 Gm., potassium iodide 10 Gm., in distilled water q. s. 100 Gm. It is a transparent liquid, deep brown, iodine odor; aqueous solution containing 4.8-5.2 p. c. of iodine, and 9.8-10.2 p. c. of potassium iodide. Test: 1. Add 1 drop to 1 Ml. (Cc.) of starch T. S. diluted with water 10 Ml. (Cc.) - deep blue color. Should be kept dark, in glass-stoppered bottles. Dose, ej-10 (.06-6 Ml. (Cc.)); mostly used externally.

2. Tinctura Iodi. Tincture of Iodine. (Syn., Tr. Iodi, Tinctura Iodinii; Fr. Teinture dTode; Ger. Jodtinktur.)

Manufacture: 7 p. c. Dissolve potassium iodide 5 Gm. in distilled water 5 Ml. (Cc), add iodine 7 Gm., agitate until solution effected, add alcohol q. s. 100 Ml. (Cc), mix thoroughly. It is an alcoholic solution of iodine, 6.5-7.5 Gm., and potassium iodide, 4.5-5.5 Gm., in the 100 Ml. (Cc). Dose, ej-5 (.06-.3 Ml. (Cc)); mostly used externally.

3. Unguentum Iodi. Iodine Ointment. (Syn., Ung. Iodi, Unguen-tum Iodinii; Fr. Pommade d'Iode; Ger. Jodsalbe.)

Manufacture: 4 p. c Triturate until dissolved iodine 4 Gm., potassium iodide 4 Gm., glycerin 12 Gm., in a glass mortar, gradually incorporate benzoinated lard 80 Gm., mix thoroughly; avoid metallic utensils and containers, and only dispense when freshly made.

Unoff. Preps.: Collodium Iodi, 5 p. c., + flexible collodion 95. Liquor lodi Phenolatus, 1/30 p. c. (comp. solution of iodine 1.5 Ml. (Cc.)), + liquefied phenol .6, glycerin 165, water q. s. 100. Petroxolinum lodi, 10 p. c, + oleic acid 40, alcohol 20, light liquid petrolatum 23, oil of lavender 2, stronger ammonia water 5. Tinctura Iodi Fortior (Churchill's Tincture), 16.5 p. c, + potassium iodide 3.3, water 25, alcohol q. s. 100. Tinctura Iodi Decolorata, 8.3 p. c, + sodium thiosulphate 8.3, water 10, stronger ammonia water 0.5, alcohol q. s. 100. Syrupus lodotannicus, .27 p. c, tannic acid .54, sugar 80, dist. water q. s. 100.

Properties. - Antiseptic, counter-irritant, causing itching, smarting of the skin, corrosive, alterative, absorbent. Rapidly absorbed by mucous membranes, in the blood combined with sodium; eliminated in urine, saliva, milk, by intestinal and nasal mucous membranes.

Uses. - Mostly external; enlarged glands, chronic abscesses, swollen joints, chilblains, ringworm, chronic pneumonia, lung affections, boils, carbuncles, suppurating glands, hydrocele, ovarian cyst, hernia, dropsy of the joints, large chronic bronchocele, chronic abscesses, fistulae, wounds of venomous serpents, bites of rabid animals, hydrocephalus, chronic dysentery, diarrhoea.

Poisoning: Have metallic taste, pain in throat and stomach, salivation, intense thirst and gastro-enteritis, vomiting, purging, pale face, suppressed urine, vertigo, faintness, feeble and rapid pulse, fever, cyanosis, swollen eyelids, convulsive movements, collapse. Give emetics, starch, flour, arrowroot mixed with water, induce vomiting, sodium bicarbonate, hypodermic ammonia, stimulants (strychnine, digitalis, alcohol, atropine), morphine, demulcents, heat.

Incompatibles: Ammonia, mineral acids, metallic salts, alkaloids, forming insoluble compounds with most of these. Iodides with mineral acids, acid salts, bismuth subnitrate, alkaloids, silver nitrate, soluble lead salts, potassium chlorate, spirit nitrous ether, licorice.