Search

Clinical Question: Are Echinacea products associated with a reduced incidence and a shorter duration of common colds compared with placebo?, Bottom Line: Individual prophylaxis trials show no association with prevention of the common cold, but exploratory meta-analysis suggests that Echinacea products may be associated with a small reduction in cold incidence. In treatment trials, there was no association of Echinacea products with a shorter duration of colds.

Background: Echinacea plant preparations (family Asteraceae) are widely used in Europe and North America for common colds. Most consumers and physicians are not aware that products available under the term Echinacea differ appreciably in their composition, mainly due to the use of variable plant material, extraction methods and the addition of other components., Objectives: To assess whether there is evidence that Echinacea preparations are effective and safe compared to placebo in the prevention and treatment of the common cold., Search Methods: We searched CENTRAL 2013, Issue 5, MEDLINE (1946 to May week 5, 2013), EMBASE (1991 to June 2013), CINAHL (1981 to June 2013), AMED (1985 to February 2012), LILACS (1981 to June 2013), Web of Science (1955 to June 2013), CAMBASE (no time limits), the Centre for Complementary Medicine Research (1988 to September 2007), WHO ICTRP and clinicaltrials.gov (last searched 5 June 2013), screened references and asked experts in the field about published and unpublished studies., Selection Criteria: Randomized controlled trials (RCTs) comparing mono-preparations of Echinacea with placebo., Data Collection and Analysis: At least two review authors independently assessed eligibility and trial quality and extracted data. The primary efficacy outcome was the number of individuals with at least one cold in prevention trials and the duration of colds in treatment trials. For all included trials the primary safety and acceptability outcome was the number of participants dropping out due to adverse events. We assessed trial quality using the Cochrane 'Risk of bias' tool., Main Results: Twenty-four double-blind trials with 4631 participants including a total of 33 comparisons of Echinacea preparations and placebo met the inclusion criteria. A variety of different Echinacea preparations based on different species and parts of plant were used. Evidence from seven trials was available for preparations based on the aerial parts of Echinacea purpurea. Ten trials were considered to have a low risk of bias, six to have an unclear risk of bias and eight to have a high risk of bias. Ten trials with 13 comparisons investigated prevention and 15 trials with 20 comparisons investigated treatment of colds (one trial addressed both prevention and treatment).Due to the strong clinical heterogeneity of the studies we refrained from pooling for the main analysis. None of the 12 prevention comparisons reporting the number of patients with at least one cold episode found a statistically significant difference. However a post hoc pooling of their results, suggests a relative risk reduction of 10% to 20%. Of the seven treatment trials reporting data on the duration of colds, only one showed a significant effect of Echinacea over placebo. The number of patients dropping out or reporting adverse effects did not differ significantly between treatment and control groups in prevention and treatment trials. However, in prevention trials there was a trend towards a larger number of patients dropping out due to adverse events in the treatment groups., Authors' Conclusions: Echinacea products have not here been shown to provide benefits for treating colds, although, it is possible there is a weak benefit from some Echinacea products: the results of individual prophylaxis trials consistently show positive (if non-significant) trends, although potential effects are of questionable clinical relevance.

This article aims to summarize the current state of knowledge on St. John's wort (Hypericum perforatum L.) which is one of the oldest and best investigated medicinal herbs. Dried alcoholic extracts are the most important preparations on the market although a variety of other preparations are available. Depressive disorders according to modern diagnostic standards are the best known and most widely investigated indication although the more traditional, broader indication of 'psycho-vegetative disorders, depressive disorders, anxiety and/or nervous agitation', including diagnoses such as somatoform disorders, might more adequately describe what Hypericum extracts are actually used for by many practitioners. The exact mechanisms of action are still unclear, but the available research clearly shows that various bioactive constituents contribute to the clinical effects reported, often in a synergistic manner. Hypericum extracts have consistently shown activity in pharmacological models related to antidepressant effects. Randomized clinical trials show that Hypericum extracts are more effective than placebo and similarly effective as standard antidepressants while having better tolerability in the acute treatment of major depressive episodes. The most important risk associated with Hypericum extracts are interactions with other drugs. Therefore, physicians need to be informed whether their patients take St. John's wort products. If the risk of interactions is adequately taken into account, high quality Hypericum extracts are an effective and safe tool in the hand of qualified health profession-als in primary care., (Copyright 2009 S. Karger AG, Basel.)

Background: In some countries extracts of the plant Hypericum perforatum L. (popularly called St. John's wort) are widely used for treating patients with depressive symptoms., Objectives: To investigate whether extracts of hypericum are more effective than placebo and as effective as standard antidepressants in the treatment of major depression; and whether they have fewer adverse effects than standard antidepressant drugs., Search Strategy: Trials were searched in computerised databases, by checking bibliographies of relevant articles, and by contacting manufacturers and researchers., Selection Criteria: Trials were included if they: (1) were randomised and double-blind; (2) included patients with major depression; (3) compared extracts of St. John's wort with placebo or standard antidepressants; (4) included clinical outcomes assessing depressive symptoms., Data Collection and Analysis: At least two independent reviewers extracted information from study reports. The main outcome measure for assessing effectiveness was the responder rate ratio (the relative risk of having a response to treatment). The main outcome measure for adverse effects was the number of patients dropping out due to adverse effects., Main Results: A total of 29 trials (5489 patients) including 18 comparisons with placebo and 17 comparisons with synthetic standard antidepressants met the inclusion criteria. Results of placebo-controlled trials showed marked heterogeneity. In nine larger trials the combined response rate ratio (RR) for hypericum extracts compared with placebo was 1.28 (95% confidence interval (CI), 1.10 to 1.49) and from nine smaller trials was 1.87 (95% CI, 1.22 to 2.87). Results of trials comparing hypericum extracts and standard antidepressants were statistically homogeneous. Compared with tri- or tetracyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs), respectively, RRs were 1.02 (95% CI, 0.90 to 1.15; 5 trials) and 1.00 (95% CI, 0.90 to 1.11; 12 trials). Both in placebo-controlled trials and in comparisons with standard antidepressants, trials from German-speaking countries reported findings more favourable to hypericum. Patients given hypericum extracts dropped out of trials due to adverse effects less frequently than those given older antidepressants (odds ratio (OR) 0.24; 95% CI, 0.13 to 0.46) or SSRIs (OR 0.53, 95% CI, 0.34-0.83)., Authors' Conclusions: The available evidence suggests that the hypericum extracts tested in the included trials a) are superior to placebo in patients with major depression; b) are similarly effective as standard antidepressants; c) and have fewer side effects than standard antidepressants. The association of country of origin and precision with effects sizes complicates the interpretation.

Echinacea preparations are widely used for common cold. Many consumers and healthcare professionals are not aware that products available under the term Echinacea may differ in their composition, due to the use of different species, plant parts, extraction methods and addition of other components. In 2005, a Cochrane review has been published to provide objective evidence whether the various Echinacea preparations are more effective than no treatment, more effective than placebo or similarly effective to other treatments in the prevention and the treatment of the common cold. In contrast to other reviews, the specific criteria for pooling of data from different trials have been predefined to assure a meaningful meta-analysis. In the meantime two further meta-analyses have been published. In the present mini-review, these latest meta-analyses are evaluated and discussed.

Background: Mistletoe extracts are commonly used in cancer patients. It is claimed that they improve survival and quality of life (QOL) in cancer patients., Objectives: To determine the effectiveness, tolerability and safety of mistletoe extracts given either as monotherapy or adjunct therapy for patients with cancer., Search Strategy: Search sources included the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 3, 2007) Cochrane Complementary Medicine Field Registry of randomized clinical trials (RCTs) and controlled clinical trials, MEDLINE, EMBASE, HEALTHSTAR, INT. HEALTH TECHNOLOGY ASSESSMENT, SOMED, AMED, BIOETHICSLINE, BIOSIS, CancerLit, CATLINE, CISCOM (August 2007). For the search the Standard Operating Procedures of the Information System in Health Economics at the German Institute for Medical Documentation and Information (DIMDI) were utilized. Reference lists of relevant articles and authors extensive files were searched for additional studies. Manufacturers of mistletoe preparations were contacted., Selection Criteria: We included RCTs of adults with cancer of any type. The interventions were mistletoe extracts as sole treatments or given concomitantly with chemo- or radiotherapy. The outcome measures were survival times, tumor response, QOL, psychological distress, adverse effects from antineoplastic treatment and safety of mistletoe extracts., Data Collection and Analysis: Three review authors independently assessed trials for inclusion in the review. All review authors independently took part in the extraction of data and assessment of study quality and clinical relevance. Disagreements were resolved by consensus. Study authors were contacted where information was unclear. Methodological quality was narratively described and additionally assessed with the Delphi list and the Jadad score. High methodological quality was defined if six out of nine Delphi criteria, or four out of five Jadad criteria were fulfilled. Results were presented qualitatively., Main Results: Eighty studies were identified. Fifty-eight were excluded for various reasons, usually as there was no prospective trial design with randomised treatment allocation. Of the 21 included studies 13 provided data on survival, 7 on tumour response, 16 on measures of QOL or psychological outcomes, or prevalence of chemotherapy-related adverse effects and 12 on side effects of mistletoe treatment; overall comprising 3484 randomised cancer patients. Interventions evaluated were 5 preparations of mistletoe extracts from 5 manufacturers and one commercially not available preparation. The general reporting of RCTs was poor. Of the 13 trials investigating survival, 6 showed some evidence of a benefit, but none of them was of high methodological quality. The results of two trials in patients with melanoma and head and neck cancer gave some evidence that the used mistletoe extracts are not effective for improving survival. Of the 16 trials investigating the efficacy of mistletoe extracts for either improving QOL, psychological measures, performance index, symptom scales or the reduction of adverse effects of chemotherapy, 14 showed some evidence of a benefit, but only 2 of them including breast cancer patients during chemotherapy were of higher methodological quality. Data on side effects indicated that, depending on the dose, mistletoe extracts were usually well tolerated and had few side effects., Authors' Conclusions: The evidence from RCTs to support the view that the application of mistletoe extracts has impact on survival or leads to an improved ability to fight cancer or to withstand anticancer treatments is weak. Nevertheless, there is some evidence that mistletoe extracts may offer benefits on measures of QOL during chemotherapy for breast cancer, but these results need replication. Overall, more high quality, independent clinical research is needed to truly assess the safety and effectiveness of mistletoe extracts. Patients receiving mistletoe therapy should be encouraged to take part in future trails.

The present contribution describes the history of the Cochrane review on St. John's wort (hypericum perforatum L.) for depression. Work for the first version started in 1993, the year that saw the official foundation of the Cochrane Collaboration, but 3 years before a pertinent Cochrane review group was established. After the registration of the Collaborative Review Group for Depression, Anxiety and Neuroses (CCDAN) and the publication of a first print version of the review that included 23 trials in 1996 the first Cochrane version with 27 trials became available in 1998. Updates were completed in 2005 (37 included trials) and 2008 (29 trials). Due to changes in selection criteria and review methods the resources needed to complete the 2005 and 2008 updates were similar to those for the first version in 1996. Only one trial included in the 1996 version is still part of the 2008 version. Despite the large number of available trials and improvements in review methodology the current evidence is more difficult to interpret than in 1996.

Background: Preparations of the plant Echinacea (family Compositae) are widely used in some European countries and in North America for common colds. Most consumers and physicians are not aware that products available under the term Echinacea differ appreciably in their composition, mainly due to the use of variable plant material, extraction methods and addition of other components., Objectives: The objective of this review was to assess whether there is evidence that Echinacea preparations are 1) more effective than no treatment; 2) more effective than placebo; 3) similarly effective to other treatments in A) the prevention and B) the treatment of the common cold., Search Strategy: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2005); PubMed (1997 to April 2005), EMBASE (1998 to June 2005), AMED (to August 2005), Centre for Complementary Medicine Research (in Munich) (1988 to May 2005), contacted experts, and screened references of reviews., Selection Criteria: We included randomized controlled trials that compared mono-preparations of Echinacea with a placebo, no treatment, or another treatment for the prevention or treatment of common colds. Trials on combinations of Echinacea and other herbs were excluded., Data Collection and Analysis: For all studies, at least two authors independently assessed eligibility and trial quality, and extracted data. Outcomes of interest in prevention trials were: numbers of individuals with one or more colds, and severity and duration of colds; and in treatment trials: total symptom scores, nasal symptoms, and duration of colds., Main Results: Sixteen trials including a total of 22 comparisons of an Echinacea preparation and a control group (19 with placebo, 2 with no treatment, 1 with another herbal preparation) met the inclusion criteria. All trials except one were described as double-blind. The majority had reasonable to good methodological quality. Three comparisons investigated prevention of colds and 19 comparisons tested treatment of colds. A variety of different Echinacea preparations were used. None of the three comparisons in the prevention trials showed an effect over placebo. Comparing an Echinacea preparation with placebo as treatment, a significant effect was reported in nine comparisons, a trend in one, and no difference in six. More than one trial was available only for preparations based on the aerial parts from Echinacea purpurea (E. purpurea)., Authors' Conclusions: Echinacea preparations tested in clinical trials differ greatly. There is some evidence that preparations based on the aerial parts of Echinacea purpurea might be effective for the early treatment of colds in adults but results are not fully consistent. Beneficial effects of other Echinacea preparations, and for preventative purposes might exist but have not been shown in independently replicated, rigorous randomized trials.

The international review board was set up as the scientific advisory body of the Swiss Complementary Medicine Evaluation Programme (PEK) in 2002. It has met several times and has given advice with respect to the most important aspects of the programme. It would have been the normal procedure for the review board to have had the opportunity to comment on the drafts of the final scientific products as well as the draft of the summary report, in order to advise on them, before the documents became publicly available and formed the basis for political decision making. But the responsible authorities changed this process. In the following, the review board comments both on this process and on the products.

Background: Extracts of the plant Hypericum perforatum L. (popularly called St. John's wort) have been used in folk medicine for a long time for a range of indications including depressive disorders., Objectives: To investigate whether extracts of hypericum are more effective than placebo and as effective as standard antidepressants in the treatment of depressive disorders in adults; and whether they have have less adverse effects than standard antidepressant drugs., Search Strategy: Trials were searched in computerized databases (Cochrane Collaboration Depression, Anxiety & Neurosis Group Clinical Trials Registers; PubMed); by checking bibliographies of pertinent articles; and by contacting manufacturers and researchers., Selection Criteria: Trials were included if they: (1) were randomized and double-blind; (2) included patients with depressive disorders; (3) compared extracts of St. John's wort with placebo or standard antidepressants; and (4) included clinical outcomes such as scales assessing depressive symptoms., Data Collection and Analysis: Information on patients, interventions, outcomes and results was extracted by at least two independent reviewers using a standard form. The main outcome measure for comparing the effectiveness of hypericum with placebo and standard antidepressants was the responder rate ratio (responder rate in treatment group/responder rate in control group). The main outcome measure for adverse effects was the number of patients dropping out for adverse effects., Main Results: A total of 37 trials, including 26 comparisons with placebo and 14 comparisons with synthetic standard antidepressants, met the inclusion criteria. Results of placebo-controlled trials showed marked heterogeneity. In trials restricted to patients with major depression, the combined response rate ratio (RR) for hypericum extracts compared with placebo from six larger trials was 1.15 (95% confidence interval (CI), 1.02-1.29) and from six smaller trials was 2.06 (95% CI, 1.65 to 2.59). In trials not restricted to patients with major depression, the RR from six larger trials was 1.71 (95% CI, 1.40-2.09) and from five smaller trials was 6.13 (95% CI, 3.63 to 10.38). Trials comparing hypericum extracts and standard antidepressants were statistically homogeneous. Compared with selective serotonin reuptake inhibitors (SSRIs) and tri- or tetracyclic antidepressants, respectively, RRs were 0.98 (95% CI, 0.85-1.12; six trials) and 1.03 (95% CI, 0.93-1.14; seven trials). Patients given hypericum extracts dropped out of trials due to adverse effects less frequently than those given older antidepressants (Odds ratio (OR) 0.25; 95% CI, 0.14-0.45); such comparisons were in the same direction, but not statistically significantly different, between hypericum extracts and SSRIs (OR 0.60, 95% CI, 0.31-1.15)., Authors' Conclusions: Current evidence regarding hypericum extracts is inconsistent and confusing. In patients who meet criteria for major depression, several recent placebo-controlled trials suggest that the tested hypericum extracts have minimal beneficial effects while other trials suggest that hypericum and standard antidepressants have similar beneficial effects. As the preparations available on the market might vary considerably in their pharmaceutical quality, the results of this review apply only to the products tested in the included studies.

Background: Extracts of Hypericum perforatum (St John's wort) are widely used to treat depression. Evidence for its efficacy has been criticised on methodological grounds., Aims: To update evidence from randomised trials regarding the effectiveness of Hypericum extracts., Methods: We performed a systematic review and meta-analysis of 37 double-blind randomised controlled trials that compared clinical effects of Hypericum monopreparation with either placebo or a standard antidepressant in adults with depressive disorders., Results: Larger placebo-controlled trials restricted to patients with major depression showed only minor effects over placebo, while older and smaller trials not restricted to patients with major depression showed marked effects. Compared with standard antidepressants Hypericum extracts had similar effects., Conclusions: Current evidence regarding Hypericum extracts is inconsistent and confusing. In patients who meet criteria for major depression, several recent placebo-controlled trials suggest that Hypericum has minimal beneficial effects while other trials suggest that Hypericum and standard antidepressants have similar beneficial effects.

We present a systematic review of observational studies of hypericum extracts in the treatment of depressive disorders. We included non-randomized studies with at least 100 patients suffering from depressive disorders treated with hypericum mono-preparations for at least 4 weeks, which reported clinical outcomes. Potentially relevant studies were identified through searches in electronic databases (Medline, PubMed), contacts with manufacturers, and handsearching of proceedings of phytomedicine congresses. Information on patients, interventions, methods an results were extracted by two reviewers. Sixteen studies including a total of 34,804 (range 101-11,296) patients met the inclusion criteria. Most studies investigated short-term effects (4-6 weeks) in patients with mild to moderate depression. Response rates (according to physician assessment) varied between 65% and 100%, the proportion of patients dropping out due to side effects varied between 0.0% and 2.8%. Two studies investigated long-term effects (52 weeks). Reponse rates were 60% and 69%, respectively, and the proportions of patients dropping out due to side effects were 3.4% and 5.7%, respectively. Serious side effects or interactions were not reported in any study. The quality of reporting was insufficient in the majority of publications. The available studies show that hypericum extract are well tolerated and seem to be effective in routine treatment of mild to moderate depressive disorders.

Objective: To obtain an overview of the available clinical evidence on safety and tolerability of hypericum extracts, we reviewed (1) dropout rates and adverse effects in double-blind randomized trials comparing hypericum extracts and placebo or synthetic standard antidepressants; (2) dropout rates and adverse effects in large-scale observational studies; and (3) adverse effects reported in published cases and to public drug surveillance agencies., Method: Data on dropout rates and adverse effects were extracted from double-blind randomized trials of hypericum monopreparations collected for a Cochrane review (last search July 2003) and from a PubMed search (text word hypericum; search dates 1998-January 2003). Similar data were extracted from uncontrolled observational studies including at least 100 patients identified through a PubMed search (search term hypericum NOT animal, last update May 2003), contacts with manufacturers, and screening of review articles. Case reports and case series on adverse events associated with hypericum products were identified through a MEDLINE search (1966-November 2002; search term: hypericum AND [adverse effects OR interaction]) and a PubMed search (February 2003) and were collected from 5 public drug surveillance agencies (data through May 2001). All database searches were conducted as English and non-English language searches., Results: Data from 35 double-blind randomized trials showed that dropout and adverse effects rates in patients receiving hypericum extracts were similar to placebo, lower than with older antidepressants, and slightly lower than with selective serotonin reuptake inhibitors. Dropout rates due to adverse effects in 17 observational studies including 35,562 patients ranged from 0% to 5.7%; interactions or serious adverse effects were not reported in any study. Published cases and cases reported to drug surveillance agencies suggest that interactions with a variety of drugs (particularly cyclosporine in transplant patients) are the most relevant adverse effects of hypericum extracts., Conclusions: The available evidence suggests that hypericum extracts are well tolerated and safe if taken under control of a physician who is aware of potentially relevant risks in specific circumstances.

Objective: To investigate the effectiveness of a clinical treatment program with traditional Chinese medicine for migraine and tension-type headache., Methods: Ninety-one patients with migraine, episodic or chronic tension-type headache according to the criteria of the International Headache Society were randomised into an experimental or a waiting list control group. Patients in the experimental group were treated 4 weeks in a hospital for traditional Chinese medicine after a baseline period of one month. Patients in the waiting list group continued their previous headache treatment. Main outcome measure was the difference in the number of days with headache of at least moderate intensity during baseline (month 1) and month 7., Results: The difference in the number of days with headache of at least moderate intensity was 5.6 (S.D., 6.1) days in the experimental group and 1.2 (S.D., 4.5) days in the waiting list group (P <0.001). A reduction of more than 50% in headache days was observed in 52% of the patients in the experimental group and 16% in the waiting list group. Patients with migraine and a combination of migraine and episodic tension-type headaches improved more than patients with other headaches., Conclusion: The results of this study indicate that treatment in the hospital for traditional Chinese medicine in Kotzting is associated with lasting improvements in the majority of patients.

Background: We aimed to describe the approaches and characteristics of systematic reviews on three major complementary therapies and to assess their methodological quality., Methods: Systematic reviews of clinical trials of acupuncture, herbal medicines, and homeopathy were identified from a database developed for the Cochrane Collaboration Complementary Medicine Field. Information on conditions, interventions, methods, results, and conclusions was extracted using a pre-tested form; methodological quality was assessed using the Oxman scale., Results: 115 reviews were included (39 on acupuncture, 58 on herbal medicine, 18 on homeopathy). Research questions were most specific in herbal medicine, and tended to be very general in homeopathy. The main comparison in most reviews was with placebo. The methodological quality of reviews was highly variable. Deficiencies were most frequent for the description of the selection process and the summary of the results of primary studies., Conclusion: Systematic reviews tend to approach different complementary therapies in different manner. Compared to a set of reviews on analgesic interventions methodological quality was slightly better on the average, but there is ample room for improvement in future complementary medicine reviews., (Copyright 2003 S. Karger GmbH, Freiburg)

In an open prospective study with matched historical controls we aimed to evaluate whether a polysaccharide fraction isolated from the herb Echinacea purpurea could counteract the undesired effects of chemotherapy. Fifteen patients with advanced gastric cancer undergoing palliative chemotherapy with etoposide, leucovorin and 5-fluorouracil (ELF) received for 10 days (beginning 3 days before chemotherapy) daily i.v. injections of 2 mg of a polysaccharide fraction isolated from Echinacea purpurea herb cell cultures (EPS-EPO VIIa). The median number of leukocytes 14-16 days after chemotherapy was 3630/microL (range 1470-5770) in the patients receiving EPS-EPO VIIa compared with 2370/microL (870-3950) in the patients of the historical control group (p = 0.015). EPS-EPO VIIa had no clinically relevant effects on phagocytic activity of granulocytes or on lymphocyte subpopulations. Sixty-eight adverse events including two deaths were observed, most likely due to chemotherapy and the general condition of the patients. However, an association with the test intervention cannot be ruled out completely. The results of this pilot study suggest that EPS-EPO VIIa might be effective in reducing chemotherapy-induced leukopenia. The efficacy and safety should be investigated in further studies., (Copyright 2002 John Wiley & Sons, Ltd.)

Background: To investigate the methodological quality of randomized controlled trials in three areas of complementary medicine., Methods: The methodological quality of 207 randomized trials collected for five previously published systematic reviews on homeopathy, herbal medicine (Hypericum for depression, Echinacea for common cold), and acupuncture (for asthma and chronic headache) was assessed using a validated scale (the Jadad scale) and single quality items., Results: While the methodological quality of the trials was highly variable, the majority had important shortcomings in reporting and/or methodology. Major problems in most trials were the description of allocation concealment and the reporting of drop-outs and withdrawals. There were relevant differences in single quality components between the different complementary therapies: For example, acupuncture trials reported adequate allocation concealment less often (6% versus 32% of homeopathy and 26% of herb trials), and trials on herbal extracts had better summary scores (mean score 3.12 versus 2.33 for homeopathy and 2.19 for acupuncture trials). Larger trials published more recently in journals listed in Medline and in English language scored significantly higher than trials not meeting these criteria., Conclusion: Trials of complementary therapies often have relevant methodological weaknesses. The type of weaknesses varies considerably across interventions.

Background: Complementary therapies are widespread but controversial. We aim to provide a comprehensive collection and a summary of systematic reviews of clinical trials in three major complementary therapies (acupuncture, herbal medicine, homeopathy). This article is dealing with herbal medicine. Potentially relevant reviews were searched through the register of the Cochrane Complementary Medicine Field, the Cochrane Library, Medline, and bibliographies of articles and books. To be included articles had to review prospective clinical trials of herbal medicines; had to describe review methods explicitly; had to be published; and had to focus on treatment effects. Information on conditions, interventions, methods, results and conclusions was extracted using a pre-tested form and summarized descriptively., Results: From a total of 79 potentially relevant reviews pre-selected in the screening process 58 met the inclusion criteria. Thirty of the reports reviewed ginkgo (for dementia, intermittent claudication, tinnitus, and macular degeneration), hypericum (for depression) or garlic preparations (for cardiovascular risk factors and lower limb atherosclerosis). The quality of primary studies was criticized in the majority of the reviews. Most reviews judged the available evidence as promising but definitive conclusions were rarely possible., Conclusions: Systematic reviews are available on a broad range of herbal preparations prescribed for defined conditions. There is very little evidence on the effectiveness of herbalism as practised by specialist herbalists who combine herbs and use unconventional diagnosis.

Background: Extracts of the plant Hypericum perforatum L. (popularly called St. John's wort) have been used in folk medicine for a long time for a range of indications including depressive disorders., Objectives: To investigate whether extracts of Hypericum are more effective than placebo and as effective as standard antidepressants in the treatment of depressive disorders in adults; and whether they have have less side effects than standard antidepressant drugs., Search Strategy: Trials were searched in computerized general (Medline, Embase, Psychlit, Psychindex) and specialized databases (Cochrane Complementary Medicine Field, Cochrane Depression & Neurosis CRG, Phytodok); by checking bibliographies of pertinent articles; and by contacting manufacturers and researchers., Selection Criteria: Trials were included if they: (1) were randomized; (2) included patients with depressive disorders; (3) compared preparations of St. John's wort (alone or in combination with other plant extracts) with placebo or other antidepressants; and (4) included clinical outcomes such as scales assessing depressive symptoms., Data Collection and Analysis: Information on patients, interventions, outcomes and results was extracted by at least two independent reviewers using a standard form. The main outcome measure for comparing the effectiveness of Hypericum with placebo and standard antidepressants was the responder rate ratio (responder rate in treatment group/responder rate in control group). The main outcome measure for side effects was the number of patients reporting side effects., Main Results: 27 trials including a total of 2291 patients met inclusion criteria. 17 trials with 1168 patients were placebo-controlled (16 addressed single preparations, one a combination with four other plant extracts). Ten trials (eight single preparations, two combinations of hypericum and valeriana) with 1123 patients compared hypericum with other antidepressant or sedative drugs. Most trials were four to six weeks long. Participants usually had "neurotic depression" or "mild to moderate severe depressive disorders." Hypericum preparations were significantly superior to placebo (rate ratio 2.47; 95% confidence interval 1.69 to 3.61) and similarly effective as standard antidepressants (single preparations 1.01; 0.87 to 1.16, combinations 1.52; 0.78 to 2.94). The proportions of patients reporting side effects were 26.3% for hypericum single preparations vs. 44.7% for standard antidepressants (0.57; 0.47 to 0.69), and 14. 6% for combinations vs. 26.5% with amitriptyline or desipramine (0. 49; 0.23 to 1.04)., Reviewer's Conclusions: There is evidence that extracts of hypericum are more effective than placebo for the short-term treatment of mild to moderately severe depressive disorders. The current evidence is inadequate to establish whether hypericum is as effective as other antidepressants. Further studies comparing hypericum with standard antidepressants in well defined groups of patients over longer observations periods, investigating long term side effects, and comparing different extracts and doses are needed.

Background: Extracts of the plant Echinacea (family Compositae) are widely used in some European countries and the USA for upper respiratory tract infections., Objectives: The objective of this review was to assess the effects of preparations containing extracts of Echinacea in the prevention and treatment of the common cold., Search Strategy: We searched the Cochrane Acute Respiratory Infections Group and Complementary Medicine Field's trials registers, MEDLINE, EMBASE, Phytodok and reference lists of articles. We also contacted researchers and manufacturers. Date of last search: Spring 1998., Selection Criteria: Randomised and quasi-randomised trials comparing preparations containing an extract of Echinacea compared with a placebo, no treatment, or another treatment for common colds., Data Collection and Analysis: At least two independent reviewers assessed trial quality and extracted data., Main Results: Sixteen trials (eight prevention trials, and eight trials on treatment of upper respiratory tract infections) with a total of 3396 participants were included. Variation in preparations investigated and methodological quality of trials precluded quantitative meta-analysis. Overall, the results suggested that some Echinacea preparations may be better than placebo., Reviewer's Conclusions: The majority of the available studies report positive results. However there is not enough evidence to recommend a specific Echinacea product, or Echinacea preparations for the treatment or prevention of common colds.

Objective: To investigate the safety and efficacy of 2 extracts of echinacea for preventing upper respiratory tract infections., Design: Three-armed, randomized, double-blind, placebo-controlled trial., Setting: Four military institutions and 1 industrial plant., Participants: Three hundred two volunteers without acute illness at time of enrollment., Interventions: Ethanolic extract from Echinacea purpurea roots, Echinacea angustifolia roots, or placebo, given orally for 12 weeks., Main Outcome Measure: Time until the first upper respiratory tract infection (time to event). Secondary outcome measures were the number of participants with at least 1 infection, global assessment, and adverse effects., Results: The time until occurrence of the first upper respiratory tract infection was 66 days (95% confidence interval [CI], 61-72 days) in the E angustifolia group, 69 days (95% CI, 64-74 days) in the E purpurea group, and 65 days (95% CI, 59-70 days) in the placebo group (P = .49). In the placebo group, 36.7% had an infection. In the treatment groups, 32.0% in the E angustifolia group (relative risk compared with placebo, 0.87; 95% CI, 0.59-1.30) and 29.3% in the E purpurea group (relative risk compared with placebo, 0.80; 95% CI, 0.53-1.31) had an infection. Participants in the treatment groups believed that they had more benefit from the medication than those in the placebo group (P = .04). Adverse effects were reported by 18 subjects in the E angustifolia group, 10 in the E purpurea group, and 11 in the placebo group., Conclusion: In this study a prophylactic effect of the investigated echinacea extracts could not be shown. However, based on the results of this and 2 other studies, one could speculate that there might be an effect of echinacea products in the order of magnitude of 10% to 20% relative risk reduction. Future studies with much larger sample sizes would be needed to prove this effect.