Non-interventional observational study broadens positive benefit-risk assessment of an immunomodulating herbal remedy in the common cold.

Background: The unique extract of a mixture of Baptisiae tinctoriae radix, Echinaceae pallidae/purpureae radix and Thujae occidentalis herba alleviates the typical symptoms of the common cold and shortens the duration of the disease. Purpose: The risk-benefit ratio of a concentrated formulation of this herbal extract was investigated under everyday conditions. Study design: Pharmacy-based, non-interventional, multicenter, open, uncontrolled study registered at DRKS00011068. Methods: For 10 days, patients completed a diary questionnaire rating the severity of each common cold symptom on a 10-point scale. For evaluation, symptoms were combined into the scores "overall severity", "rhinitis", "bronchitis" and "general symptoms". Cox models were used to evaluate the influence of covariates on the time of stable improvement. Results: In total 955 patients (12 to 90 years) were analyzed; 85% assessed the efficacy as good or very good. Response (improvement of the overall severity by at least 50%) was reached at median day 5 (95% CImedian 5-5). General symptoms abated faster than the other complaints. The percentage of predominantly moderate or severe symptoms to predominantly mild or absent symptoms reversed on day 3.9 (interpolation). Results of adolescents and adults did not differ (p = .6013; HR = 0.918). Concomitant medication did not boost the effect of the herbal remedy. Early start of treatment of the cold accelerated the recovery (p = .0486; HR = 0.814). Thirty-four cases of adverse events were self-recorded in the diaries; none of them were serious. The tolerability was assessed as "good or very good" by 98% of the patients. Conclusion: The benefit-risk assessment of this herbal extract clearly remains positive. This non-interventional study accords with and shows transferability of the results of previous placebo-controlled studies with this extract in a real-life setting.

Risk assessment of free hydroquinone derived from Arctostaphylos Uva-ursi folium herbal preparations.

Uva-ursi folium (bearberry leaf) has been traditionally used to treat symptoms of lower urinary tract infections. The most representative constituent of this herbal drug is arbutin that is rapidly absorbed in the small intestine and undergoes hepatic conjugation to form hydroquinone (HQ) conjugates. As free HQ is crucial for the safety of the herbal preparation, we reviewed published and unpublished experimental and human studies to clarify some outdated assumptions and to support the safety of therapeutic daily doses of Uva-ursi folium extract. Specifically, data on pharmacokinetics and the human exposure of arbutin and HQ were reviewed. A therapeutic recommended human daily dose of bearberry leaf extract (420 mg hydroquinone derivatives calculated as anhydrous arbutin) liberates free HQ in urine at a maximum exposure level of 11 µg/kg body weight (bw)/d. By means of an experimental no observed effect level value, a permitted daily exposure dose below which there is a negligible risk to human health was estimated for free HQ (100 µg/kg bw/d). Dietary sources of arbutin/HQ that are regularly consumed long term by humans generate comparable free HQ exposure levels. There is no direct evidence, regarding human data, supporting the fact that free HQ causes convulsion, hepatotoxicity, nephrotoxicity, or promotion of tumors in humans. Free HQ had no activity promoting pancreatic, bladder, stomach, or liver carcinogenesis. In conclusion, under the recommended use conditions Uva-ursi folium is a safe therapeutic option for treating lower urinary tract infections.

Suspected black cohosh hepatotoxicity: no evidence by meta-analysis of randomized controlled clinical trials for isopropanolic black cohosh extract.

OBJECTIVE: Black cohosh, a popular herbal treatment for menopausal symptoms, has been implicated in a number of hepatotoxicity case reports. The purpose of this investigation was to analyze data gained from clinical trials on the effect of black cohosh on liver function. METHODS: A meta-analysis of randomized, double-blind, and controlled clinical trials was conducted. These studies primarily evaluated the efficacy and safety of the isopropanolic black cohosh extract (iCR) in perimenopausal and postmenopausal women. Raw data on liver function values of aspartate aminotransferase, alanine aminotransferase, and γ-glutamyltranspeptidase were considered in this analysis, if these data at baseline and after 3 to 6 months of treatment were available. Standard methods of descriptive statistics were used in this analysis. RESULTS: Five studies involving a total of 1,117 women were included in the meta-analyses. A total of 1,020 women (test population=517 and reference population=503) completed the studies. Perimenopausal and postmenopausal women (40-60 y) were treated daily with iCR (corresponding to 40-128 mg drug) for 3 to 6 months. The meta-analyses of the standardized mean differences in the "test" versus "reference" showed no significant effects and no differences between double-blind, placebo-controlled and other trials. The overall fixed effect ± SEM was 0.055 ± 0.062 (P=0.37) for aspartate aminotransferase and 0.063 ± 0.062 (P=0.31) for alanine aminotransferase. The nonsignificant effects concerned the overall analyses of all included studies as well as the proportion of placebo-controlled studies. CONCLUSIONS: The results of this meta-analysis of five randomized, double-blind, and controlled clinical trials showed no evidence that iCR has any adverse effect on liver function.

Thuja occidentalis (Arbor vitae): A Review of its Pharmaceutical, Pharmacological and Clinical Properties.

Arbor vitae (Thuja occidentalis L.) is a native European tree widely used in homeopathy and evidence-based phytotherapy. Many reviews and monographs have been published on the herbal substance's description, mode of action and clinical use. However, no comprehensive evidence-based review is available. Therefore, our aim was to search MEDLINE databases and survey manufacturers for further details or unpublished data. This review presents the botany, ethnobotany and phytochemistry, especially the different contents of essential oil (Thujone) in relation to different extraction procedures of this medicinal plant. Thuja's antiviral action and immunopharmacological potential, such as stimulatory and co-stimulatory effects on cytokine and antibody production and activation of macrophages and other immunocompetent cells, have been evaluated in numerous in vitro and in vivo investigations. Although no controlled trials have been conducted on Thuja occ alone, many clinical studies have been performed with a herbal medicinal product containing a special extract of Thuja occ and other immunostimulants, demonstrating its therapeutic efficacy and safety in respiratory tract infections.