The leaves and flowering tops of Eupatorium perfoliatum.

Characters. - Leaves opposite, united at base, lanceolate, from four to six inches (10 to 15 centimetres) long, tapering, crenately serrate, rugosely veined, rough above, downy and resinous, dotted beneath; flower-heads corymbed, numerous, with an oblong involucre of lance-linear scales, and with from ten to fifteen white florets, having a bristly pappus in a single row; odour weak and aromatic; taste astringent and bitter.

Composition. - It contains a volatile oil and a bitter glucoside, eupatorin.

Preparation.

Dose.

Extractum Eupatorii Fluidum......................................................

15-30 min.

Use. - It is used as a tonic and diaphoretic. In large doses it causes catharsis and emesis. As a tonic it is employed in dyspepsia and general debility. As a diaphoretic it is used to prevent any bad consequences from exposure to cold, and to cut short an attack of catarrh or muscular rheumatism at its commencement. It may then be given as infusion or as fluid extract mixed with hot water. When given in large doses as an emetic and cathartic, it is useful in causing the expulsion of tape-worm.