Characters. - In pieces three or four inches long, about the size of a small quill, contorted and irregularly annulated. Colour, brown of various shades. It consists of two parts, the cortical or active portion, which is brittle, and a slender tough white woody centre. Powder pale brown, with a faint nauseous odour, and a somewhat acrid and bitter taste.

Impurities. - (1) Hemidesmus, which is cracked, but not annulated; (2) Almond meal (in powdered ipecacuanha), detected by odour of prussic acid when moistened.

Composition. - Ipecacuanha contains from 1/4 to 1 per cent. of emetin, which is its active principle; ipecacuanhic or cephaelic acid; starch, gum, etc. Emetin, C20H30NO5, is a crystalline alkaloid, white, becoming yellow, odourless, bitter, comparatively insoluble in water, forming salts with acids which are readily dissolved in ordinary media.

Dose. - As an expectorant, 1/2 to 2 gr.; as an emetic, 15 to 30 gr.

Preparations.

1. Pulvis Ipecacuanhae Compositus. "Dover's Powder." Ipecacuanha, 1; Opium, 1; Sulphate of Potash, 8. A light fawn-coloured powder. Lose, 5 to 10 gr.

From Lover's Powder is prepared:

Pilula Ipecacuanhae; cum Scilla. - Compound Powder of Ipecacuanha, 3; Squill, 1; Ammoniacum, 1; Treacle, q.s. Dose, 5 to 10 gr.

2. Pilula Conii Composita

Pilula Conii Composita. 1 in 6. See Conii Folia.

3. Trochisci Ipecacuanhae

Trochisci Ipecacuanhae. 1/4 gr. in each. Lose, 1 to 3.

4. Trochisci Morphiae Et Ipecacuanhae

Trochisci Morphiae Et Ipecacuanhae. Ipecacuanha, 1/12 gr.:

Hydrochlorate of Morphia, 1/36 gr. in each. Bet Opium, page l87.

5. Vinum Ipecacuanhae

Vinum Ipecacuanhae. 1 in 20 of Sherry. Dose, 5 to 40 min. as an expectorant; as an emetic, 3 to 6 dr.

Action And Uses. 1. Immediate Local Action And Uses

Externally. - Ipecacuanha powder is irritant, and even pustulant, but is never used to produce this effect. Exposed mucous membranes are similarly affected by it. If taken as snuff it causes irritation of the nerves, sneezing, and reflex mucous secretion; and the same effect follows its application in smoke or spray to the pharynx, larynx, or lower air-passages; in some persons it excites asthma. In the form of a spray of the diluted vinum, or inhaled as the smoke of the burning powder, it is used to relieve cough due to dryness or deficient secretion of the throat and air passages.

Internally. - Reaching the stomach, ipecacuanha in very small doses (gr.1/4 ) is a gastric stimulant doubtless increasing the local circulation and secretion. It is therefore a useful addition to bitter stomachic and tonic mixtures, and will even arrest vomiting due to certain obscure conditions of the gastric nerves. The compound powder is of the greatest value in ulceration of the stomach, and some forms of dyspeptic vomiting. In larger doses (15 to 30 gr.) it acts as an emetic, partly by a direct effect upon the stomach, and partly by exciting the vomiting centre in the medulla (indirect emesis). This important subject will be discussed under the heading of the specific action.

In the intestines, ipecacuanha is still a stimulant, increasing the flow of mucus; and in large doses an irritant. A remarkable tolerance of the drug is, however, readily established in many persons suffering from dysentery, in which disease ipecacuanha has the power of arresting the inflammatory action in the bowel, checking the liquid and bloody evacuations, and often effects a complete cure. For this purpose enormous doses (30 to 90 gr.) are given, or large doses frequently repeated (20 gr. every two hours).

2. Action In The Blood

Emetin passes through the blood, from the alimentary canal to the tissues, but is not positively known to affect it.

3. Specific Action And Uses

Ipecacuanha (emetin) acts on the vomiting centre in the medulla, i.e. is an indirect emetic, this effect being added to the direct (gastric) action already mentioned. The ordinary doses (15 to 30 gr. of the powdered root, 3 to 6 fl.dr. of the vinum for adults) produce free evacuation of the stomach, and respiratory passages in 20 to 30 minutes, the dose often having to be repeated in 15 minutes, and the vomiting act probably occurring but once. But little nausea precedes, and moderate depression follows, the emesis. The circulation and respiration are disturbed and finally depressed by ipecacuanha, chiefly through the vomiting.

This drug is suitable as an emetic in cases where the necessity for evacuation of the stomach is not very urgent, and the subject is likely to be benefited by moderate but injured by great depression. It must not be given, therefore, in poisoning by alkaloids, such as morphia, but to children and weakly subjects in cases where the after effects of the drug will be also useful. It thus occupies a position amongst emetics between sulphate of zinc or copper and tartar emetic. Ipecacuanha may be used to empty the stomach in the early stages of sthenic fevers (less commonly than before); in cramp, whooping-cough, and the bronchitis of children, to expel membranes or mucous products from the air passages; and in acute dyspepsia with biliousness and heat of skin.

The skin is stimulated to increased secretion by ipecacuanha, which is used as a diaphoretic, especially combined with opium (Dover's Powder), in common colds, sore throat, and mild rheumatic attacks.

4. Remote Local Action And Uses

Emetin is excreted by the various mucous membranes, including those of the bronchi, the stomach, and bowels, and by the liver. On the bronchi it produces the same remote as immediate local action, namely, stimulation of the nerves, reflex cough, increased secretion, and, in large doses. even inflammation of the mucous membrane and lungs. Ipecacuanha is thus an expectorant, increasing at once the expulsive acts, and the amount, that is, the liquidity, of the sputa: It is the most generally used of all this class of measures, being given in acute and chronic bronchitis, in phthisis, and in most cases of cough when the phlegm is scanty and tough. Important advantages of ipecacuanha are, that, if taken in excess, it causes sickness, which is often beneficial in the bronchitis of children; and that as a diaphoretic and moderate depressant of the circulation, i.e. a sedative expectorant, it controls the fever at the same time.

Acting remotely on the liver, this drug is a direct chola-gogue, increasing the secretion of bile; and has long been a favourite constituent of some purgative pills and aperient draughts for chronic biliousness and gouty dyspepsia.