A gum-resinous exudation from the stem, after being punctured by beetles, of Dorema Ammoniacum. Persia and the Punjaub.

Characters. - In roundish tears or irregular masses formed by their agglomeration without any intervening dark-coloured substance. The tears are roundish, pale yellowish-brown externally, milk-white internally, brittle. Peculiar odour, bitter, acrid, nauseous taste. It is coloured yellow by caustic potash, and a solution of chlorinated soda gives it a bright orange hue.

Composition. - Gum resin and volatile oil. Dose. - 10 to 30 grains.

Preparations.

B.P.

Dose.

Emplastrum Ammoniaci cum Hydrargyro..................................

for external use.

" Galbani ......................................................................

Mistura Ammoniaci (1/4 oz., water 8 fl. oz.)..................................

1/2-1 fl. oz.

Pilula Scillae Composita (vide p. 523)............................................

" Ipecacuanhae cum Scilla (vide p. 522).................................

U.S.P.

Emplastrum Ammoniaci..................................................................

for external use.

„ cum Hydrargyro..............

Mostura Ammoniaci (4, water 100)................................................

2 fl. dr. or more.

Use. - It is used for the same purposes as galbanum, chiefly as a stimulant to the mucous membrane in bronchorrhoea.