This section is from the book "A Text-Book Of Pharmacology, Therapeutics And Materia Medica", by T. Lauder Brunton. Also available from Amazon: A text-book of pharmacology, therapeutics and materia medica.
Iodine. - A non-metallic element obtained from the ashes of sea-weeds and from mineral iodides and iodates.
Preparation. - Vide p. 548.
Reaction. - The aqueous solution strikes a deep blue colour with starch.
Tests. - .It should not adhere to the sides of the bottle, and its solution in chloroform should be clear and limpid (absence of moisture). It sublimes as a purple vapour without leaving any residue (absence of fixed impurities), and the portion that first comes over does not include any slender colourless prisms emitting a pungent odour (absence of cyanide of iodine); 12.7 grains dissolved in an ounce of water containing fifteen grains of iodide of potassium require for complete discoloration 1,000 grain-measures of the volumetric solution of hyposulphite of sodium.
Emplastrum Plumbi Iodidi.
Hydrargyri Iodidum Eubrum.
Linimentum Iodi (p. 516).
Linimentum Potassii Iodidi cum Sapone (p. 516). Liquor Iodi, aqueous solution (1 in
Syrupus Ferri Iodidi.
Tinctura Iodi, alcoholic solution (1 in 40). Unguentum Hydrargyri Iodidi Rubri. * „ Iodi (1 in 31).
„ Plumbi Iodidi.
„ Potassii Iodidi.
,, Sulphuris Iodidi.
*Vapor Iodi (Tincture of Iodine, 1 fl. dr. mixed with 1 fl. oz. of water, gently warmed, and the vapour inhaled).
Sulphuris Iodidum. Tinctura Iodi (8 in 100). *Unguentum Iodi (4 in 100).
„ Plumbi Iodidi.
„ Potassii Iodi.
The preparations marked with * in the preceding list contain iodine in a free state dissolved by the aid of iodide of potassium (p. 556). Tinctura Iodi U.S.P. contains free iodine dissolved in alcohol. The others contain it in a state of combination.
U.S.P. Liquor Iodi Compositus. Iodine 5, iodide of potassium 10, distilled water 85. This solution differs from Liquor Iodi P.B., only in containing 10 per cent. of iodide of potassium, while the B.P. preparation contains 7 1/2 per cent.