Pharmacovigilance of herbal medicines

Safety profile of herbal medicines submitted for marketing authorization in Tanzania: a cross-sectional retrospective study

BACKGROUND

The popular use of herbal medicines necessitates national regulatory authorities to have efficient mechanisms for the control of these products including marketing authorization (MA) and safety follow-up. Herbal medicines like conventional medicines require assessment of efficacy, safety and quality information before MA can be granted. However, the complete proof of safety is mainly based on the history of the long-term traditional use. Herbal medicines can cause adverse reactions due to various factors and thus require clinical trials to ensure their safety. Herbal medicines treatment practices involve combinations of different plants to achieve the desired effect while multiple herbal components have been known to cause herbal-herbal toxicity and interactions due to variety of complex active ingredients in plants. Compliance with regulatory requirements on herbal medicines has been shown to be difficult for manufacturers since different countries have different regulatory requirements with wide variations which results in the MA of very few herbal medicines. Limited studies on dossiers of marketing authorization of herbal medicines have been performed in other countries, with no studies in African regulatory system settings. The aim of this study is to determine the type of safety documentation that is submitted on herbal medicines application dossiers to support MA in Tanzania.

METHODS

A cross-sectional retrospective study of herbal medicines dossiers submitted at the Tanzania Medicines and Medical Devices Authority from 2009 to 2020 was conducted.

RESULTS

As many as 75% of the herbal products applications were combination products made by more than one herbal substance or plant. Out of 84 dossiers subjected to analysis the majority did not provide evidence of preclinical (55%) and clinical safety data (68%). Evidence of safety data in humans was mostly from the literature (70%) and not manufacturers' clinical studies. Quality parameters with safety implications were not included in 48% and 23% of the active herbal substance and finished product specifications, respectively.

CONCLUSION

Analysis of the herbal medicine dossiers submitted showed major deficiencies of safety data to support MA. Manufactures need to provide evidence to support the safety of their products for evidence-based regulatory decisions and to avoid multiple reviews of the applications.

Pharmacovigilance of herbal medicines: Concerns and future prospects

ETHNOPHARMACOLOGICAL RELEVANCE

The use of herbal medicines for prophylaxis, prevention, and treatment of various ailments is rising throughout the world because they are thought to be safer than allopathic treatments, which they are. However, several investigations have documented the toxicity and adverse drug reactions (ADR) of certain formulations and botanicals if not consumed wisely.

AIM OF THE STUDY

The goal of the current study is to address herbal medication pharmacovigilance (PV) modeling and related considerations for improved patient safety. Also, focus is laid on the comprehensive and critical analysis of the current state of PV for herbal medications at the national and international levels.

MATERIALS AND METHODS

Targeted review also known as focused literature review methodology was utilized for exploring the data from various scientific platforms such as Science Direct, Wiley Online Library, Springer, PubMed, Google Scholar using "pharmacovigilance, herbal medicine, traditional medicine, ADR, under reporting, herb toxicity, herb interactions" as keywords along with standard literature pertaining to herbal medicines that is published by the WHO and other international and national organizations etc. The botanical names mentioned in the present article were authenticated using World Flora Online database.

RESULTS

The historical developments paving the way for PV in regulatory setup were also discussed, along with various criteria's for monitoring herbal medicine, ADR of herbs, phytoconstituents, and traditional medicines, herb-drug interactions, modes of reporting ADR, databases for reporting ADR's, provisions of PV in regulatory framework of different nations, challenges and way forward in PV are discussed in detail advocating a robust drug safety ecosystem for herbal medicines.

CONCLUSION

Despite recent efforts to encourage the reporting of suspected ADRs linked to herbal medicines, such as expanding the programme and adding community pharmacists and other healthcare professionals as recognized reporters, the number of herbal ADR reports received by the regulatory bodies remains comparatively low. Since users often do not seek professional advice or report if they have side effects, under-reporting, is anticipated to be significant for herbal medications. There are inadequate quality control methods, poor regulatory oversight considering herbs used in food and botanicals, and unregulated distribution channels. In addition, botanical identity, traceability of herbs, ecological concerns, over-the-counter (OTC) herbal medicines, patient-physicians barriers requires special focus by the regulatory bodies for improved global safety of herbal medicines.

Analysis of 16 mycotoxins in genuine traditional Chinese medicine for five medicinal parts: Classification of analytical method based on PANI@CS extraction-UPLC-MS/MS

A novel PANI@CS solid-phase dispersive extractant combined with ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was developed for the first time, which was used for high-throughput, multi-component, real-time online rapid pretreatment and quantitative classification of 16 mycotoxins from five different medicinal parts of 13 genuine traditional Chinese medicines (TCMs). Ultra performance liquid chromatography combined with triple quadrupole mass spectrometry was used for separation and ESI detection. An internal standard isotope matching calibration was used for quantification purposes to compensate for matrix effects. The limits of detection (LOD) of 16 mycotoxins ranged from 0.1 to 6.0 μg/kg. The linear coefficients (R²) were ≥0.996 in the linear range from 10.0 to 200 μg/L. The recoveries of the 16 mycotoxins ranged from 90.1% to 105.8%, and the relative standard deviations (RSDs) ranged from 1.3% to 4.1%. Thirteen TCMs from five representative medicinal parts were selected and tested under the best sample preparation procedure and chromatographic analysis conditions. The results showed that the method could improve the sensitivity and accuracy of the sample analysis, improve the selectivity and reproducibility of the decolorization and purification of TCMs, which is suitable for the practical application of mycotoxin in trace analysis. This method can also provide a new idea for accurate, efficient, rapid and multi-component online detection of mycotoxins for quality and safety control of TCMs.

Implications for herbal polypharmacy: coumarin-induced hepatotoxicity increased through common herbal phytochemicals astragaloside IV and atractylenolide I

Hepatotoxicity is a well-known adverse effect of many substances, with toxicity often resulting from interactions of drugs with other drug-like substances. With the increased availability of complementary and alternative medicines, including herbal medicines, the likelihood of adverse interactions between drugs and drug-like substances in herbs increases. However, the impact of potential herb-herb interactions is little understood. To assess the potential of two cytochrome P450 enzyme modulating phytochemicals common to many herbal medicines, atractylenolide I (ATR-I) and astragaloside IV (AST-IV), to interact with coumarin, another phytochemical common in many foods, a hepatocyte function model with a liver carcinoma cell line, HepG2, was exposed to these agents. To determine the effects of cytochrome P450 modulation by these phytochemicals certain cells were induced with rifampicin to induce cytochrome P450. Increasing concentrations of ATR-I combined with a fixed, nontoxic concentration of coumarin (200 µM), demonstrated significant additive interactions. 300 µM ATR-I produced a 31% reduction in cell viability (p < 0.01) with coumarin in rifampicin uninduced cells. In rifampicin-induced cells, ATR-I (100-300 µM) produced a significant reduction in cell viability (p < 0.01) with coumarin (200 µM). AST-IV with fixed coumarin (200 µM) showed 27% toxicity at 300 µM AST-IV in rifampicin uninduced cells (p < 0.05) and 30% toxicity in rifampicin induced cells (p < 0.05). However, when fixed coumarin and AST-IV were combined with increasing concentrations of ATR-I no further significant increase in toxicity was observed (p > 0.05). These results demonstrate the potential toxic interactive capabilities of common traditional Chinese herbal medicine phytochemicals and underline the potential importance of coumarin-mediated toxicity.

Alpha-Glucosidase Inhibitory Assay-Screened Isolation and Molecular Docking Model from Bauhinia pulla Active Compounds

The aim of this research was to establish the constituents of Bauhinia pulla as anti-diabetic agents. A phytochemistry analysis was conducted by chromatographic and spectroscopic techniques. The alpha-glucosidase inhibitory assay screening resulted in the isolation of eight known compounds of quercetin, quercitrin, luteolin, 5-deoxyluteolin, 4-methyl ether isoliquiritigenin, 3,2',4'-trihydroxy-4-methoxychalcone, stigmasterol and β-sitosterol. Ethanol leaf extracts showed potential effects, which led to a strong inhibitory activity of isolated quercetin at 138.95 µg/mL and 5.41 µg/mL of IC₅₀, respectively. The docking confirmed that flavonoids and chalcones had the same potential binding sites and responsibilities for their activity. This study was the first report of Bauhinia pulla chemical constituents and its alpha-glucosidase inhibition.

Genotoxicity Study of Vitex megapotamica (Spreng.) Moldenke

Vitex megapotamica (Spreng) Moldenke is commonly known as tarumã, it is an important medicinal and edible fruit plant. It is native to regions of tropical and subtropical climate in greater proportion than temperate zones and widely distributed in Central America, South America, Asia, and Africa. In Brazil, it is present in the Atlantic Forest and Cerrado biomes. Despite its widespread use, there are no minimum standards for quality control or information on genotoxicity. Therefore, the aim of this study was to present a detailed description of the short-term genotoxicity assays of V. megapotamica and to provide parameters of a preparation routinely used in traditional folk medicine. For genotoxicity assays, five groups were used with eight wistar rats in each group. For this, three doses of the V. megapotamica extract in doses (100, 300, and 900 mg/kg) or negative control (filtered water) were administered orally and positive control cyclophosphamide monohydrate (20 mg/kg; Sigma-Aldrich^®) was applied by the intraperitoneal route after 24 h. At the end, whole blood was collected in a tube containing EDTA for the comet test and later the animals were euthanized. For the micronucleus test, femurs were removed, and bone marrow was collected. In the comet assay, V. megapotamica crude extract did not show significant DNA damage at all doses tested. The micronucleus assay showed no significant increase in the frequency of inducing micronuclei at any dose examined. It can be concluded that the safety parameters in genotoxicity studies reveal that V. megapotamica has no toxicity, which characterizes the important quality control of this plant species.

Development of a Specific Mini-Barcode From Plastome and its Application for Qualitative and Quantitative Identification of Processed Herbal Products Using DNA Metabarcoding Technique: A Case Study on Senna

Herbal products play an important role globally in the pharmaceutical and healthcare industries. However, some specific groups of herbal products are easily adulterated by confused materials on the market, which seriously reduces the products’ quality. Universal conventional DNA barcodes would function poorly since the processed herbal products generally suffer from varying degrees of DNA degradation and DNA mixing during processing or manufacturing. For quality control purposes, an accurate and effective method should be provided for species identification of these herbal products. Here, we provided a strategy of developing the specific mini-barcode using Senna as an example, and by coupling with the metabarcoding technique, it realized the qualitative and quantitative identification of processed herbal products. The plastomes of Senna obtusifolia (L.) H.S.Irwin & Barneby and Senna occidentalis (L.) Link were newly assembled, and the hypervariable coding-regions were identified by comparing their genomes. Then, the specific mini-barcodes were developed based on the identified hypervariable regions. Finally, we applied the DNA metabarcoding technique to the developed mini-barcodes. Results showed that the lengths of plastomes of S. obtusifolia and S. occidentalis were 162,426 and 159,993 bp, respectively. Four hypervariable coding-regions ycf1, rpl23, petL, and matK were identified. Two specific mini-barcodes were successfully developed from matK, and the mini-barcode of primer 647F-847R was proved to be able to qualitatively and quantitatively identify these two processed Senna seeds. Overall, our study established a valuable way to develop the specific mini-barcode, which may provide a new idea for the quality control of processed herbal products.

The governance of traditional medicine and herbal remedies in the selected local markets of Western Kenya

BACKGROUND

A lot of emphasis is often placed on modern governance systems and little or no attention is given to traditional governance practices which remain largely undocumented. The study aimed at finding out important traditional and modern governance practices that regulate traditional medicine sector in Western Kenya.

MATERIALS AND METHODS

The study was carried out in selected market centres of Western Kenya where the identified traditional medicine practitioners (TMPs) sell their traditional medicine. All consenting TMPs and professional experts were interviewed with the aid of a semi-structured questionnaire. Purposive sampling design with elements of snowball techniques was employed in tracing competent traditional medicine (TM) experts and relevant professional experts. The data collected was processed in Microsoft Excel and descriptive statistics performed. Pearson's chi-square statistics was carried out to determine the significance of the traditional and modern governance data sets using the STATA software.

RESULTS

Modern governance practices were not significantly different in all the market centres surveyed (p = 0.080). Equally, the traditional governance practices were also not significantly different in all the selected market centres (p = 1.000).

CONCLUSIONS

Traditional governance practices play an important role in the governance of traditional medicine and are shaped by the socio-cultural beliefs of the local communities. Modern governance practices, on the other hand, are widely perceived as top downregulation of the traditional medicine growing industry.

Cherry stem infusions: antioxidant potential and phenolic profile by UHPLC-ESI-QTOF-MS

This study highlights not only the antioxidant potential of cherry stem infusion but also the need to globally harmonize the control and regulation of herbal products.

What Future Healthcare Professionals Need to Know About Pharmacovigilance: Introduction of the WHO PV Core Curriculum for University Teaching with Focus on Clinical Aspects

Adverse drug reactions (ADRs) can cause serious health problems, as shown in studies about drug-related hospitalizations. To build knowledge of and raise awareness about ADRs among healthcare professionals, more education in the field of ADRs and pharmacovigilance (PV) is needed. No standard exists for teaching PV at universities for medical, pharmacy, dentistry and nursing students, so a core curriculum needs to be developed to teach important aspects of PV to students. In September 2016, a stakeholders' meeting was initiated on behalf of the World Health Organization (WHO) and organized by the Netherlands Pharmacovigilance Centre Lareb. This meeting addressed and agreed on the PV competencies students need to develop and what key aspects of the subject should be taught. Five key aspects were identified: understanding the importance of PV in the context of pharmacotherapy, and preventing, recognizing, managing and reporting ADRs. Since time and resources for PV education are limited, elements of the WHO PV core curriculum for university teaching were designed to be integrated into existing courses but can be used as a stand-alone programme. The basis of and outline for the WHO PV core curriculum for university teaching are addressed in this paper. It is expected that PV competencies for students are vital for their contribution to safe use of medicines in the future. In addition, this article aims to stimulate discussion on this subject and promote collaboration between universities, national PV centres and other stakeholders to integrate key aspects of PV in their educational programmes.

Subchronic Toxicity Studies of Cortex Dictamni Extracts in Mice and Its Potential Hepatotoxicity Mechanisms in Vitro

Cortex Dictamni is a commonly-used traditional Chinese herbal medicine for the treatment of skin inflammation, tinea, and eczema. Recently, some studies reported that Cortex Dictamni might induce liver injury, suggesting more attention to its safety. The current study was designed to investigate subchronic toxicity of Cortex Dictamni aqueous extract (CDAE) and ethanol extract (CDEE) in mice and the potential hepatotoxicity mechanisms in vitro. Firstly, CDAE or CDEE groups were administrated with varying dosages (2.3, 4.6, or 9.2 g/kg/day, p.o.) in mice for 28 days in subchronic toxicity studies. General clinical signs and biochemical parameters were examined, and morphological analyses were conducted. Secondly, we identified the different constituents of CDAE and CDEE using HPLC-MS/MS and chose major components for further study. In order to determine the toxic components, we investigated the cytotoxicity of extracts and chosen components using CCK-8 assay in HepG2 cells. Furthermore, we explored the possible hepatotoxicity mechanisms of Cortex Dictamni using a high content analysis (HCA). The results showed that no significant differences of general clinical signs were observed in mice. Aspartate alanine aminotransferase (ALT) and aminotransferase (AST) were significantly increased in the high-dose CDAE and CDEE groups compared to the control group. Meanwhile, the absolute and relative liver weights and liver/brain ratio were significantly elevated, and histological examination of liver demonstrated cellular enlargement or nuclear shrinkage. In UPLC analysis, we compared the chemical constituents between CDAE and CDEE, and chose dictamnine, obakunone, and fraxinellone for hepatotoxicity evaluation in the in vitro studies. In the CCK-8 assay, CDAE, CDEE, dictamnine, obakunone, and fraxinellone decreased the cell viability in a dose-dependent manner after treatment for 48 h. Furthermore, the cell number decreased, while the nuclear intensity, cell membrane permeability, and concentration of reactive oxygen species were shown to increase, meanwhile, mitochondrial membrane potential was also changed in HepG2 cells following 48 h of compounds treatment using HCA. Our studies suggested that CDAE and CDEE have potential hepatotoxicity, and that the alcohol extraction process could increase toxicity. Dictamnine, obakunone, and fraxinellone may be the possible toxic components in Cortex Dictamni with dictamnine as the most potentially hepatotoxic component, whose potential hepatotoxicity mechanism may be associated with cell apoptosis. Moreover, this study could provide valuable data for clinical drug safety research of Cortex Dictamni and a good example for safety study of other Chinese herbal medicines.

Ethnoveterinary perspectives and promising future

In this review, we have discussed the recent potential effects of plants and their derivatives in treating diseases of veterinary importance in livestock. The therapeutic value of these natural products depends upon their bioactive metabolites that are developed and isolated from crude plants, thus produced a selective action on the body. The crises of drug resistance in most pathogenic bacteria and parasites that cause economic loss in animals necessitate developing new sources for drugs to overcome therapeutic failure. We summarized the different antibacterial and antiparasitic plants with their bioactive compounds that have widely used in animals. Finally, the environmental friendly feed additives that may be used as alternatives to an antibiotic growth promoter for broiler chickens were illustrated.

Subchronic oral toxicity study of Habb-e-Suranjan in albino Wistar rats

Background

Habb-e-Suranjan(HS) is a Unani pharmacopoeial formulation used for treatment of rheumatoid arthritis. The present study was carried to evaluate the toxic potential of HS in albino Wistar rats.

Methods

The subchronic was carried out at the dose levels of 2440 mg/kg of body weight in both sexes. The rats were observed carefully for any behavioral change for next 24 hours (hr) after the administration of the drug and daily twice thereafter till the completion of experimentation. Water/feed consumption and body weight were recorded on weekly basis. The rats were sacrificed on 91st day after overnight fasting. Blood was collected for hematological and biochemical analysis. The rats were dissected and organs were observed for any morphological changes. Organ samples were collected for histological studies.

Results

There were no incidences of mortality/morbidity found in any of the treated rats.HScaused no significant difference in the body weights as well as relative organs weights of treated groups when compared with the control groups. There were no significant changes found in any biochemical, hematological and histopathological parameters that could indicate any signs of toxicity.

Conclusions

The study suggests thatHSis safe and did not induce any adverse effect in rats.

Comparative toxicity study on classical and modified version of Jawarish Jalinoos (a traditional Unani formulation) in rats

BACKGROUND

Jawarish Jalinoos (JJ) is a classical semisolid traditional Unani formulation clinically used for the treatment of weakness of vital organs, liver, and stomach. Although JJ has been widely used clinically for several decades, no scientific report is available for its safety.

METHODS

JJ and its sugar-free tablet version (SFJJ; formulated to target diabetic population) were assessed for safety in rats. Ninety-day repeated dose oral toxicity study was performed as per the Organisation for Economic Co-operation and Development Guideline 408. JJ was orally administered at the dose of 2000 mg/kg bw/d, whereas SFJJ was orally administered at the doses of 506 mg/kg body weight (bw)/d, 1012 mg/kg bw/d, and 2024 mg/kg bw/d for 90 days. The animals were periodically observed for clinical signs of toxicity, mortality, morbidity, body weight changes, and feed consumption. At the end of the study, hematology, clinical biochemistry, electrolytes, gross pathology, relative organ weight, and histological examination were performed.

RESULTS

Treatment with SFJJ and JJ showed no significant differences in body weight gain, feed consumption, hematology, clinical biochemistry, and serum electrolytes. No gross pathological findings and differences in relative organ weights were observed between control and drug treated rats. Histological examination revealed no toxicologically significant abnormalities related with SFJJ or JJ treatment.

CONCLUSION

The 90-day repeated dose oral toxicity study demonstrates that the no observed adverse effect level of SFJJ and JJ is greater than 2024 mg/kg bw/d and 2000 mg/kg bw/d (p.o.) in rats, respectively. Both formulations were found to be safe up to the tested dose levels and experimental conditions, and therefore safe for clinical use as specified in the literature.

Professional ethics in complementary and alternative medicines in management of Parkinson's disease

The practice of complementary and alternative medicine (CAM) is not, at present, considered an integral part of conventional medicine. As the popularity of CAM grows and access to information about CAM increases through the media and internet where CAMs are often promoted, patients are at risk of exposure unvalidated information. Therefore, there is a need for physicians to examine objectively the efficacy and safety of CAM, compare it with current medications, and become actively involved in the CAM treatment with patients. In accordance with these needs, this manuscript reviews the utility, scientific evidence, safety and cost-effectiveness of CAM in the treatment of Parkinson's disease (PD). We also address the ethical issues of CAM practices.

Community Pharmacists' Views and Practices Regarding Natural Health Products Sold in Community Pharmacies

BACKGROUND

Reports of regulatory and evidentiary gaps have raised concerns about the marketing and use of natural health products (NHPs). The majority of NHPs offered for sale are purchased at a community pharmacy and pharmacists are "front-line" health professionals involved in the marketing and provision of NHPs. To date, the involvement of pharmacists in pharmacy care involving NHPs and the degree to which concerns over the safety, efficacy, marketing and regulation of NHPs are addressed in pharmacy care in Canada have not been studied.

METHODS

Using Qualtrics, a web-based data collection and analysis software, and a study instrument made up of fifteen (15) open-ended, closed and rating scale questions, we surveyed the attitudes and practices of 403 community pharmacists in the Canadian province of Alberta regarding NHPs offered for sale in community pharmacies.

RESULTS

The majority of pharmacists surveyed (276; 68%) recommend NHPs to clients sometimes to very often. Vitamin D, calcium, multivitamins, prenatal vitamins, probiotics and fish oil and omega-3 fatty acids were the most frequently recommended NHPs. The most common indications for which NHPs are recommended include bone and musculoskeletal disorders, maintenance of general health, gastrointestinal disorders and pregnancy. Review articles published in the Pharmacist's Letter and Canadian Pharmacists Journal were the primary basis for recommending NHPs. The majority of pharmacists surveyed (339; 84%) recommend the use of NHPs concurrently with conventional drugs, while a significant number and proportion (125; 31%) recommend alternative use. Pharmacists in the study overwhelmingly reported providing counselling on NHPs to clients based on information obtained mainly from the Natural Medicines Comprehensive Database.

CONCLUSIONS

The study findings indicate a high prevalence of pharmacy care relating to NHPs among study participants. Although pharmacists' practices around NHPs are consistent with the existing licensing framework, we found some involvement in problematic practices that necessitate further research and potential policy scrutiny. The study also uncovered patterns of recommendations, including sources relied on in recommending NHPs and in providing counselling to patients, that raise concerns about the quality and credibility of NHP-related care provided to pharmacy patrons.