Acidum Meconicum. Meconic Acid.

Related entry: Cotarnine

C7H4O7, 3H2O = 254.08.

Meconic acid, HC7H3O7, 3H2O, is obtained from opium. It occurs in almost colourless crystals. The aqueous solution is acid in reaction, and gives a red colour with ferric chloride, the colour not being discharged by hydrochloric acid, nor by mercuric chloride (distinction from thiocyanate). It should be free from alkaloids.

Slightly soluble in water, readily soluble in alcohol.

Action and Uses.—Meconic acid has been described as a mild narcotic, but it has little or no physiological action, and is not now used medicinally. Its chemical reactions are of importance in toxicology as a valuable indication of the presence of opium.


The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.