Leptandra, or Culver's Root, consists of the dried rhizome and roots of Veronica virginica, Linn., also known as Leptandra virginica, Nutt. (N.O. Scrophularineae), a tall perennial herb, abundant in Eastern and Central North America. It is official in the U.S.P. The rhizome is horizontal or oblique, dark greyish-brown in colour, 10 to 15 centimetres long and about 5 millimetres thick. It is terminated by the remains of the aerial stem, and bears such remains at distant intervals. The numerous wiry roots are attached to the under surface, the upper surface bearing small, brown cataphyllary leaves. The rhizome is hard and woody, a transverse section exhibiting a narrow, dark cortex, a paler ring of wood of about equal thickness, and a large, dark pith or sometimes a partly hollow centre. The drug is odourless, with an unpleasantly bitter and slightly acrid taste.
Constituents.—The rhizome contains 3: 4-dimethoxycinnamic acid, mannitol, glucose, the phytosterol verosterol, cinnamic and p-methoxycinnamic acids in the form of esters, and a mixture of fatty acids.
Action and Uses.—Leptandra is a reputed cholagogue, supposed to promote the flow of bile without irritating the intestine. It has been specially recommended in duodenal indigestion and chronic constipation. Its reputation is founded upon the use of the resinoid "leptandrin,'' which is a constituent of many American nostrums. It is prepared by pouring a concentrated tincture of leptandra into water, washing the precipitated resinoid with more water, then drying and powdering it. The product is dark brown in colour, soluble in alcohol, and tasteless when pure. The statement that the drug contains a glucoside, leptandrin, has not been confirmed. The fresh rhizome is violently cathartic and emetic, but these properties are less pronounced in the dried drug. It should be kept for a year before it is used. The resinoid "leptandrin" is used in pill form, in doses of 1 to 3 decigrams (2 to 5 grains), with other so-called cholagogues or liver stimulants, and is the preparation intended when "leptandrin" is ordered in prescriptions. It is most frequently combined with podophyllin or euonymin, extract of henbane or belladonna being added to prevent griping.
Dose.—1 to 4 grammes (15 to 60 grains).
- Extractum Leptandrae, U.S.P.—EXTRACT OF LEPTANDRA.
- Fluidextract of, leptandra, 100; liquorice root, in powder, sufficient to produce 25. The fluidextract is evaporated to dryness on a water-bath at a temperature not exceeding 70°, the product reduced to powder, and sufficient powdered liquorice added to make the finished extract weigh 25. Average dose.—25 centigrams (4 grains).
- Fluidextractum Leptandrae, U.S.P.—FLUIDEXTRACT OF LEPTANDRA.
- Leptandra, in No. 60 powder, 100; alcohol (71 per cent.), sufficient to produce 100. Average dose.—1 mil (15 minims).