Ephedra also ephedrine content

Ephedra was also sold in combination with many other herbs in obscure combinations. Labels frequently listed 10 or 15 different herbs, but, analysis usually disclosed only the ephedra alkaloids and caffeine as present in sufficient quantities to be physiologically active. After several well-publicized accidental deaths, products clearly intended for abuse, such as herbal ecstasy, and other look-alike drugs (products usually containing ephedrine or phenylpropanolamine designed to look like illicit methamphetamine, but in concentrations higher than recommended by industry or the FDA) were withdrawn from the market. Labels on these products were frequently misleading. For example, one might suppose that a product called Ephedrine 60 contained 60 mg of ephedrine when, in fact, the actual ephedrine content was 25 mg. 

For commercial Ephedra the British Pharmaceutical Codex, 1934, specifies a total alkaloidal content of not less than 1-25 per cent, when assayed by the method therein prescribed. The proportion of Z-ephedrine is generally about 70 per cent. Methods of assay for total alkaloids are described by Feng and Read and by Krishna and Chose, who discuss the various difficulties involved and comments on these and other methods have been made by various workers. Conditions affecting the results of such assays have also been discussed by T ang and Wang, and Brownlee has shown that chloroform is not a suitable medium for the assay since it converts ephedrine quickly and 0-ephedrine slowly to the hydrochloride. 

Besides Ephedra species, low amounts of ephedrine can also be found in the leaves of the Malvaceae Sida cordifolia (Linn) (known as country mallow), with less than 2 % of content [2, 3] and in the Chinese herb Pinellia (known as ban xia), with around 0.003 % of ephedrine [4, 27]. Due to the low content of ephedrine, no stimulatory effects were observed in pharmacological tests with Pinellia, showing the opposite effect of sedation [28]. In addition to other species previously mentioned, other monoamine alkaloids can be found in khat (Catha edulis Forsk.) such as norpseudoephedrine and norephedrine [29, 30]. 

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