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At least 19 recordsLinked to original sources
PubMed2004

Ephedra-containing dietary supplements in the US versus ephedra as a Chinese medicine.

Ephedra has been commonly used in traditional Chinese medicine (TCM) without significant adverse effects. Ephedra-containing dietary supplements are widely used in the United States to promote weight reduction and energy enhancement. However, there are significant safety concerns regarding the use of ephedra-containing dietary supplements, especially when such use occurs by consumers without medical supervision. This article reviews and contrasts the usage of ephedra as a dietary supplement in the US against an herbal medication in TCM. The potential adverse effects of ephedra-containing dietary supplements are also reviewed.

Adverse Drug Reaction Reporting Systems↗
PubMed1993

[Discriminative stimulus properties of ephedra herb (Ephedra sinica) in rats].

The stimulus properties of ephedra herb (drug of Chinese medicine) were demonstrated in rats trained to discriminate between 2.5 ml/kg extract of ephedra herb and same volume of distilled water (p.o.). On the discrimination training, animals were shaped on an FR20 schedule to respond to one of two levers for food reinforcement when they were administrated ephedra herb extract, and to respond to the other lever when they were treated with distilled water. Cumulative dosing tests for the discriminative stimulus properties consisted of two to five trials of FR20 schedule; responses for both levers were reinforced. d-Methamphetamine 1.43 mg/kg p.o. indicated complete generalization to the ephedra herb. Nicotine and caffeine indicated modest generalization, but some animals generalized completely. These results suggest that the ephedra herb has d-methamphetamine-like, but unique discriminative stimulus properties.

Animals↗
PubMed2006

Sequence analysis of chloroplast chlB gene of medicinal Ephedra species and its application to authentication of Ephedra Herb.

Chloroplast chlB gene encoding subunit B of light-independent protochlorophyllide reductase was amplified from herbarium and crude drug specimens of Ephedra sinica, E. intermedia, E. equisetina, and E. przewalskii. Sequence comparison of the chlB gene indicated that all the E. sinica specimens have the same sequence type (Type S) distinctive from other species, while there are two sequence types (Type E1 and Type E2) in E. equisetina. E. intermedia and E. prezewalskii revealed an identical sequence type (Type IP). E. sinica was also identified by digesting the chlB fragment with Bcl I. A novel method for DNA authentication of Ephedra Herb based on the sequences of the chloroplast chlB gene and internal transcribed spacer of nuclear rRNA genes was developed and successfully applied for identification of the crude drugs obtained in the Chinese market.

Base Sequence↗
PubMed1991

[Determination of six Ephedra alkaloids in Chinese Ephedra (Ma Huang) by gas chromatography].

Six Ephedra alkaloids, namely ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, methylephedrine and methylpseudoephedrine, in 12 species of Chinese Ephedra were successfully separated and determined by gas chromatography with the highly specific and sensitive nitrogen phosphorus detector (GC/NPD). The column used (HP-5) had a cross linked 5% phenylmethylsilicone phase. Diphenylamine was used as the internal standard to check the reproducibility of the extraction yields of the alkaloids, the stability of the detector response and to quantify the alkaloids. The contents of the six alkaloids were calculated according to their regression equations. The way for the preparation of crude drug samples was improved, the diethyl ether extract of the alkalized crude sample was directly analysed by GC. The method is simple, rapid and sensitive. The results are in agreement with those of the HPLC method.

Alkaloids↗
PubMed2003

Efficacy and safety of ephedra and ephedrine for weight loss and athletic performance: a meta-analysis.

CONTEXT: Ephedra and ephedrine sometimes are used for weight loss or enhanced athletic performance, but the efficacy and safety of these compounds are uncertain. OBJECTIVE: To assess the efficacy and safety of ephedra and ephedrine used for weight loss and enhanced athletic performance. DATA SOURCES: We searched 9 databases using the terms ephedra, ephedrine, adverse effect, side effect, efficacy, effective, and toxic. We included unpublished trials and non-English-language documents. Adverse events reported to the US Food and Drug Administration MedWatch program were assessed. STUDY SELECTION: Eligible studies were controlled trials of ephedra or ephedrine used for weight loss or athletic performance and case reports of adverse events associated with such use. Eligible studies for weight loss were human studies with at least 8 weeks of follow-up; and for athletic performance, those having no minimum follow-up. Eligible case reports documented that ephedra or ephedrine was consumed within 24 hours prior to an adverse event or that ephedrine or an associated product was found in blood or urine, and that other potential causes had been excluded. Of the 530 articles screened, 52 controlled trials and 65 case reports were included in the adverse events analysis. Of more than 18 000 other case reports screened, 284 underwent detailed review. DATA EXTRACTION: Two reviewers independently identified trials of efficacy and safety of ephedra and ephedrine on weight loss or athletic performance; disagreements were resolved by consensus. Case reports were reviewed with explicit and implicit methods. DATA SYNTHESIS: No weight loss trials assessed duration of treatment greater than 6 months. Pooled results for trials comparing placebo with ephedrine (n = 5), ephedrine and caffeine (n = 12), ephedra (n = 1), and ephedra and herbs containing caffeine (n = 4) yielded estimates of weight loss (more than placebo) of 0.6 (95% confidence interval, 0.2-1.0), 1.0 (0.7-1.3), 0.8 (0.4-1.2), and 1.0 (0.6-1.3) kg/mo, respectively. Sensitivity analyses did not substantially alter the latter 3 results. No trials of ephedra and athletic performance were found; 7 trials of ephedrine were too heterogeneous to synthesize. Safety data from 50 trials yielded estimates of 2.2- to 3.6-fold increases in odds of psychiatric, autonomic, or gastrointestinal symptoms, and heart palpitations. Data are insufficient to draw conclusions about adverse events occurring at a rate less than 1.0 per thousand. The majority of case reports are insufficiently documented to allow meaningful assessment. CONCLUSIONS: Ephedrine and ephedra promote modest short-term weight loss (approximately 0.9 kg/mo more than placebo) in clinical trials. There are no data regarding long-term weight loss, and evidence to support use of ephedra for athletic performance is insufficient. Use of ephedra or ephedrine and caffeine is associated with increased risk of psychiatric, autonomic, or gastrointestinal symptoms, and heart palpitations.

Anti-Obesity Agents↗
PubMed2005

The severity of toxic reactions to ephedra: comparisons to other botanical products and national trends from 1993-2002.

OBJECTIVE: Ephedra is a botanical product widely used to enhance alertness, as a weight loss aide, and as a decongestant. Its reported adverse effects led the Food and Drug Administration (FDA) to ban ephedra-containing products in the United States in 2004. This study's purpose was to compare toxicity from botanical products containing ephedra to nonephedra products. METHODS: The Toxic Exposure Surveillance System (TESS), a national poison center database, was utilized to determine the number and outcomes of cases involving botanical products reported from 1993-2002. Cases listing both a botanical product and any other drugs or chemicals were excluded a priori. Ten-year hazard rates (moderate outcomes + major outcomes + deaths per 1000 exposures) were used to compare botanical product categories. RESULTS: There were 21,533 toxic exposures with definitive medical outcomes reported over the 10 yrs where a botanical product was the only substance involved. Of these, 4306 (19.9%) had moderate or major medical outcomes and there were two deaths, for an overall hazard score of 200 per 1000 exposures. The number of ephedra reports to poison centers increased 150-fold over the 10-yr period. The hazard rate for products that contained only ephedra was 250 per 1000 exposures and 267 per 1000 exposures for products that contained ephedra and additional ingredients; whereas the hazard score for only nonephedra botanical products was 96 per 1000 exposures. The rate ratios for multibotanical products with ephedra (RR 1.33; 95% C.I. 1.27-1.40) and for single-ingredient ephedra products (RR 1.25; 95% C.I. 1.11-1.40) were both two to six times higher than those of other common botanical products. Yohimbe-containing products had the highest hazard score (417) and rate ratio (2.08; 95% C.I. 1.59-2.80). CONCLUSION: Ephedra-containing botanical products accounted for a significant number of toxic exposures with severe medical outcomes reported to poison centers. Hazard rate analysis suggests poison center-reported events involving ephedra-containing botanical products were much more likely to result in severe medical outcomes than those involving nonephedra-containing botanical products. These data support recommendations by policymakers that the sale of ephedra should be prohibited to protect consumers. Our data suggest that the botanical product, yohimbe, may also be associated with unacceptably high risks of toxicity and should receive close scrutiny from health policymakers.

Data Collection↗
PubMed2006

Studies on cultivated ephedra plants in inner mongolia autonomous region and ningxia hui autonomous region.

Progression of the desertification in northern China has been causing damage to wild Ephedra plants on which we depend for most of supply of the traditional herbal medicine, "Ma huang." The Chinese government encourages the cultivation of Ephedra plants, and Ephedra fields have been reclaimed in the original Ephedra habitats in recent years. We surveyed 7 Ephedra fields that have been recently developed in the Inner Mongolia Autonomous Region and Ningxia Hui Autonomous Region to collect information on Ephedra plant cultivation, especially pertaining to crop species. Specimens taken from those Ephedra fields were genetically and morphologically analyzed, and their ephedrine alkaloid content was examined. DNA analyses of Ephedra specimens, including DNA sequencing of ITS (internal transcribing sequence of nuclear ribosomal DNA) and trn L/F (intron of trnL and intergenic spacer between the trnL and trnF of chloroplast DNA) region and species-specific amplification of trn L/F were conducted to identify Ephedra species. Based on the results of DNA sequencing and morphological determination, the crops grown in 6 fields ware identified as Ephedra sinica, while co-planting of E. sinica and E. intermedia was found in one field where a higher appearance rate of plants with varied morphology from wild Ephedra plants was observed. Furthermore, direct sequencing of the PCR product of the trn L/F region of some specimens from the field and their species-specific PCR showed ambivalent result. Cloning and sequencing of the PCR product of the trn L/F region of those specimens DNA suggested their heteroplasmy, containing both E. sinica- and E. intermedia-type chloroplasts. On the other hand, the profile of the ephedrine alkaloid content was clearly correlated with the result of direct sequencing of the trn L/F region; the specimens showing the E. sinica-type sequence contained more ephedrine than pseudoephedrine, and the specimens of the E. intermedia-type more pseudoephedrine.

China↗
PubMed2006

Analysis of ephedra-free labeled dietary supplements sold in the San Francisco Bay area in 2003.

OBJECTIVE: To sample dietary supplements (DS) labeled as ephedra-free to evaluate whether products met their labeling claim. METHODS: One control DS product containing ephedra alkaloids and 29 DS labeled as ephedra-free were purchased from various retail locations in San Francisco. All products were sent to the California Department of Health Services (CDHS), Food and Drug Laboratory for content and quantity analysis. All laboratory personnel were blinded to product names and labeled contents. All DS products were screened for the presence of undeclared drugs, ephedra alkaloids, and heavy metals including lead, arsenic, cadmium and mercury. All products were also evaluated for compliance with the labeling requirements of the Dietary Supplement Health and Education Act (DSHEA) of 1994. RESULTS: None of the DS labeled as ephedra-free tested positive for the presence of ephedra alkaloids; as expected, the control product did test positive. Heavy metals were detected in three ephedra-free labeled DS products. All 24 products that tested positive for caffeine listed caffeine or a botanical source of caffeine on the DS label. All but two products were in compliance with DS labeling as required by DSHEA. CONCLUSIONS: This study demonstrates that manufacturers met their labeling claims for ephedra-free products. Special attention should be given to the presence of heavy metals and other drugs like caffeine, synephrine, and botanical sources of caffeine as these ingredients have replaced ephedra.

Alkaloids↗
PubMed2004

Concentrations of ephedra alkaloids and caffeine in commercial dietary supplements.

Dietary supplements that contain Ma Huang (ephedra alkaloids) and guarana (caffeine) are widely marketed and used in the U.S. for weight loss and athletic performance enhancement, despite a lack of adequate research on the pharmacology of these botanical stimulants. We developed and applied a novel liquid chromatography-tandem mass spectrometry (LC-MS-MS) method to quantitate the various ephedra alkaloids found in dietary supplements that contain Ephedra species. The quantities of ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, methylephedine, methylpseudoephedrine, and caffeine were determined for 35 commercial dietary supplements and compared with the amounts listed on the product labels. The total ephedra alkaloid content ranged from 5.97 mg to 29.3 mg per serving. Two supplement brands did not list the quantity of ephedra alkaloids on the label, and four did not list the amount of caffeine per serving. Of the products tested, 31% contained > 110% of the total ephedra alkaloids listed on the label, and 6% of the supplements contained < 90% of the listed amount. For caffeine, 86% of the product lots that listed the caffeine amount contained less than 90% of the labeled quantity. No products contained > 110% of the declared caffeine content. The total ephedra alkaloid content varied significantly from lot to lot in 5 of 9 products. Three product brands contained proportions of alkaloids that exceeded amounts reported for E. sinica, including one that was 98% ephedrine, one that had 10% norpseudoephedrine, and one that contained an average of 13% methylephedrine. We conclude that product inconsistency is common among some commercially available dietary supplements that contain ephedra alkaloids and caffeine.

Alkaloids↗
PubMed2004

Safety of ephedra: lessons learned.

The safe use of ephedra represents the best possible outcome of a convergence of variables, some with troubling potential outcomes. Commercially used ephedra and its products is prepared from Ephedra spp. and as such is subject to a variety of influences (including differences in species and strain; growth, harvest and storage conditions) all of which may influence the content of constituents (which may, in turn, affect the absorption, distribution, and metabolism of active constituents) and taken together, influences the net pharmacological effect. Further, as a natural substance with an easily perceived and desirable (i.e. weight-loss) pharmacological effect, ephedra is also susceptible to a variety of adulterants, both economic and efficacious. All of the foregoing represent potential for misadventure before ephedra even reaches the consumer. The consumer introduces a constellation of variables as well, including, but not limited to, acute and chronic diseases, inborn errors in metabolism, simultaneous use of prescription and over-the-counter drugs, dietary supplements, alcohol, illicit substances and certain foods (e.g. chocolate, caffeinated drinks), all or some of which may exert synergistic, additive or even antagonistic influences on the desired physiologic outcome. The foregoing not withstanding, the majority of the published nonclinical and clinical studies, and history of use, support the safety of ephedra at the proposed use levels. However, the reports of adverse events submitted to FDA raise concern about the risk associated with ephedra without establishing a direct causal relationship. Given the foregoing, how best can a decision on safety be made? Should the question actually be "can ephedra be as toxic as reported?"

Anti-Asthmatic Agents↗
PubMed2006

Former diversity of Ephedra (Gnetales): evidence from Early Cretaceous seeds from Portugal and North America.

BACKGROUND AND AIMS: The extant species of the seed plant group Gnetales (Ephedra, Gnetum and Welwitschia) have been considered a remnant of a much greater, now extinct, diversity due to the pronounced differences in form and ecology among the genera. Until recently, this hypothesis has not been supported by evidence from the fossil record. This paper adds to the expanding information on Gnetales from the Early Cretaceous and describes coalified seeds from Barremian-Albian localities in Portugal and USA. METHODS: The fossils were extracted from sediment samples by sieving in water. Adhering mineral matrix was removed by chemical treatment. Seeds were investigated using light and scanning electron microscopy. Morphology and anatomy of the seeds were documented and compared with those of extant species. KEY RESULTS: The fossils share characters with extant Ephedra, for example papillae on the inner surface of the seed envelope and in situ polyplicate pollen grains that shed the exine during germination. They differ from extant Ephedra seeds in morphological and anatomical details as well as in their smaller size. Two new species of Ephedra are described together with one species assigned to a new genus of Gnetales. Other Ephedra-like seeds, for which pollen and critical morphological details are currently unknown, are also present in the samples. CONCLUSIONS: These Cretaceous seeds document that key reproductive characters and pollen germination processes have remained unchanged within Ephedra for about 120 million years or more. There is sufficient variety in details of morphology to suggest that a diversity of Ephedra and Ephedra-like species were present in the Early Cretaceous flora. Their presence in Portugal and eastern North America indicates that they were widespread on the Laurasian continent. The fossil seeds are similar to seeds of Erdtmanithecales and this supports the previously suggested relationship between Erdtmanithecales and Gnetales.

Biological Evolution↗