Prep. Made by precipitating a clear solution of acetate of lead by means of iodide of potassium. In this process iodide of lead and acetate of potash are formed by double decomposition.

Prop. & Comp. Iodide of lead occurs in a yellow powder, or in crystalline scales, soluble in boiling water, forming a colourless solution, depositing crystals in cooling. Fuses and sublimes yellow, but soon gives off violet vapours from decomposition. Composition (Pb I). It is altered a little by light.

Off. Prep. Unguentum Plumbi Iodidi. Ointment of Iodide of Lead. (Iodide of lead, one ounce; lard, eight ounces. Rub them together.)

Therapeutics. Externally applied, iodide of lead acts as a mild stimulant, and has been used in the form of ointments to enlarged scrofulous joints, etc. It is seldom used internally, but has been given in scrofulous tumours.

Dose. 1/4 gr. to 1 gr., or more.