Natural Health Product Interactions with Medication

Knowledge and Beliefs about Herb/Supplement Consumption and Herb/Supplement-Drug Interactions among the General Population, including Healthcare Professionals and Pharmacists: A Systematic Review and Guidelines for a Smart Decision System

The increased consumption of a variety of herbs/supplements has been raising serious health concerns. Owing to an inadequate understanding of herb/supplement-drug interactions, the simultaneous consumption of these products may result in deleterious effects and, in extreme cases, even fatal outcomes. This systematic review is aimed at understanding the knowledge and beliefs about the consumption of herbs/supplements and herb/drug-supplement interactions (HDIs). The study follows the PRISMA guidelines. Four online databases (Web of Science; PubMed; Cochrane; and EBSCOhost) were searched, and a total of 44 studies were included, encompassing 16,929 participants. Herb and supplement consumption is explained mostly by the reported benefits across multiple conditions and ease of use. Regarding HDIs, most people take both herbs/supplements and prescription drugs simultaneously. Only a small percentage of participants have knowledge about their interaction effects, and many reported adverse interactions or side effects. Nevertheless, the main reason for stopping the prescribed drug intake is the perceived lack of its effect, and not due to interactions. Therefore, it is important to increase the knowledge about supplement use so that further strategies can be elaborated to better detect or be alert for whenever a potentially dangerous reaction and/or interaction may occur. This paper raises awareness regarding the need for developing a decision support system and ends with some considerations about the development of a technological solution capable of detecting HDIs and, thereby, aiding in the improvement of pharmacy services.

Bioactive Compounds of the Mediterranean Diet as Nutritional Support to Fight Neurodegenerative Disease

Neurodegenerative disorders are a widespread cause of morbidity and mortality worldwide, characterized by neuroinflammation, oxidative stress, and neuronal depletion. They include selective malfunction and progressive loss of neurons, glial cells, and neural networks in the brain and spinal cord. There is an urgent need to develop new and more effective therapeutic strategies to combat these devastating diseases because, today, there is no treatment that can cure degenerative diseases; however, we have many symptomatic treatments. Current nutritional approaches are beginning to reflect a fundamental change in our understanding of health. The Mediterranean diet may have a protective effect on the neurodegenerative process because it is rich in antioxidants, fiber, and omega-3 polyunsaturated fatty acids. Increasing knowledge regarding the impact of diet on regulation at the genetic and molecular levels is changing the way we consider the role of nutrition, resulting in new dietary strategies. Natural products, thanks to their bioactive compounds, have recently undergone extensive exploration and study for their therapeutic potential for a variety of diseases. Targeting simultaneous multiple mechanisms of action and a neuroprotection approach with the diet could prevent cell death and restore function to damaged neurons. For these reasons, this review will be focused on the therapeutic potential of natural products and the associations between the Mediterranean-style diet (MD), neurodegenerative diseases, and markers and mechanisms of neurodegeneration.

Comprehensive Review on Neuro-degenerative Type 3 DM

According to research, Alzheimer's disease (AD) is considered a metabolic illness caused by defective insulin signaling, insulin resistance, and low insulin levels in the brain. Type 3 diabetes has been postulated for AD because reduced insulin signaling has molecular and physiological consequences that are comparable to type I and type 2 diabetes mellitus, respectively. The similarities between type 2 diabetes and Alzheimer's disease suggest that these clinical trials might yield therapeutic benefits. However, it is important to note that lowering your risk of Alzheimer's dementia, whether you have diabetes or not, is still a multidimensional process involving factors like exercise, smoking, alcohol, food, and mental challenges. The current aim is to show that the relationship between T3D and AD is based on both the processing of amyloid-β (Aβ) precursor protein toxicity and the clearance of Aβ, which are the results of impaired insulin signaling. The brain's metabolism, with its high lipid content and energy needs, places excess demands on mitochondria and appears more susceptible to oxidative damage than the rest of the body. Current data suggests that increased oxidative stress relates to amyloid-β (Aβ) pathology and the onset of AD.

Pain management in hemophilia: expert recommendations

INTRODUCTION

As a typical consequence of bleeding into muscles and joints, patients with severe hemophilia suffer from acute and chronic pain. In spite of its high prevalence, pain in this patient group is not always sufficiently considered or treated in an effective manner.

AIM

The recommendations presented in this paper address possible improvements in pain management in hemophilia patients and particularities that have to be taken into account in this patient group.

METHOD

The manifold aspects of pain management in hemophilia patients were discussed within the framework of an expert meeting. Based on the available literature and the experts' clinical experience, the participants developed a set of recommendations presented in this paper.

RESULTS

Pain management in patients with hemophilia is often insufficient, a fact that not only influences the patients' quality of life but also implies the risk of difficult to manage chronic pain. Both the prevalent polypharmacy (due to comorbidities) as well as the underlying disease itself present special challenges to pain therapy in this patient group. The present review and recommendations are intended to support medical professionals in recognising the risks of pain chronicity, applying basic principles of multimodal pain therapy, including the options of psychological intervention and modalities of physical medicine in therapy concepts, and reaching a comprehensive understanding of the range of analgesic options available.

Herb-drug interactions and toxicity: Underscoring potential mechanisms and forecasting clinically relevant interactions induced by common phytoconstituents via data mining and computational approaches

Herbals in the form of medicine are employed extensively around the world. Herbal and conventional medicine combination is a potentially dangerous practice mainly in comorbid, hepato insufficient and frail patients leading to perilous herb-drug interactions (HDI) and toxicity. This study features potential HDI of 15 globally famous plant species through data mining and computational methods. Several plant species were found to mimic warfarin. Phytochemicals from M. charantia induced hypoglycemica. M. chamomila and G. biloba possessed anticoagulant activities. S. hispanica reduces postprandial glycemia. R. officinalis has been reported to inhibit the efflux of anticancer substrates while A. sativum can boost the clearance of anticancer agents. P. ginseng can alter blood coagulation. A cross link of the biological and in silico data revealed that a plethora of herbal metabolites such as ursolic and rosmarinic acid among others are possible/probable inhibitors of specific CYP450 enzymes. Consequently, plant species/metabolites with a given pharmacological property/metabolizing enzyme should not be mixed with drugs having the same pharmacological property/metabolizing enzyme. Even if combined with drugs, herbal medicines must be used at low doses for a short period of time and under the supervision of a healthcare professional to avoid potential adverse and toxic effects.

The need for European harmonization of Nutrivigilance in a public health perspective: a comprehensive review

According to the European Union regulation, some countries have established a pre-market notification system for food supplements while others have not. As this regulation is unfulfilled, a notified and marketed food supplement ingredient in one country may be forbidden in another. Even though food supplements shall not be placed on the market if unsafe, some products may still expose the consumers to risks. The risk is increased by easier access due to worldwide dissemination fostered by the internet and free movement of goods in the European Union. The Rapid Alert System for Food and Feed and the Emerging Risks Exchange Network are described. To date, the European Union legislation does not include a provision to establish a dedicated vigilance system for food supplements (Nutrivigilance). Six European Union countries have nevertheless set up national systems, which are presented. The present lack of European Union data collection harmonization, does not allow easy cooperation between countries. This article advocates for creating a coordinated European Nutrivigilance System to detect and scrutinize adverse effects of food supplements. This, to help in directing science-based risk assessments and reinforce the science-based decision of policy makers to improve public health safety.

[Pain treatment in old age: special features and recommendations]

BACKGROUND

For geriatric patients with chronic pain, a comprehensive well-coordinated pain management is pivotal to ensure the best possible pain relief and to minimize as far as possible preventable negative side effects of treatment.

OBJECTIVE

Description of the difficulties in pain management of geriatric patients with respect to general basic rules that are worth paying attention to and presentation of pharmacological and non-pharmacological treatment options.

METHODS

This article describes the special features of pain management in older patients and gives recommendations on the use of analgesics and potential drug interactions in geriatric patients with organ dysfunction. Furthermore, individual substance groups are described with respect to their use in geriatric patients based on the recent literature.

CONCLUSION

The aim of an individualized pain treatment in older and multimorbid patients is the relief of pain to an appropriate level, preservation of mobility, self-reliance and autonomy of each individual. The ability to participate in social activities as well as improvement in the quality of life need to be the focus of pharmacological and non-pharmacological treatment.

Characterization of red ginseng-drug interaction by CYP3A activity increased in high dose administration in mice

Ginseng (Panax ginseng Meyer) is a popular traditional herbal medicine used worldwide. Patients often take ginseng preparations with other medicines where the ginseng dose could exceed the recommended dose during long-term administration. However, ginseng-drug interactions at high doses of ginseng are poorly understood. This study showed the possibility of herb-drug interactions between the Korean red ginseng (KRG) extract and cytochrome P450 (CYP) substrates in higher administration in mice. The CYP activities were determined in vivo after oral administration of KRG extract doses of 0.5, 1.0, and 2.0 g/kg for 2 or 4 weeks by monitoring the concentration of five CYP substrates/metabolites in the blood. The area under the curve for OH-midazolam/midazolam catalysed by CYP3A was increased significantly by the administration of 2.0 g/kg KRG extract for 2 and 4 weeks. CYP3A-catalysed midazolam 1'-hydroxylation also increased significantly in a dose- and time-dependent manner in the S9 fraction of mouse liver which was not related to induction by transcription. Whereas CYP2D-catalysed dextromethorphan O-deethylation decreased in a dose- and time-dependent manner in vivo. In conclusion, interactions were observed between KRG extract and CYP2D and CYP3A substrates at subchronic-high doses of KRG administration in mice.

Retrospective Study of Reported Adverse Events Due to Complementary Health Products in Singapore From 2010 to 2016

The objective of this study is to collate and analyse adverse event reports associated with the use of complementary health products (CHP) submitted to the Health Sciences Authority (HSA) of Singapore for the period 2010-2016 to identify various trends and signals for pharmacovigilance purposes. A total of 147,215 adverse event reports suspected to be associated with pharmaceutical products and CHP were received by HSA between 2010 and 2016. Of these, 143,191 (97.3%) were associated with chemical drugs, 1,807 (1.2%) with vaccines, 1,324 (0.9%) with biological drugs (biologics), and 893 (0.6%) with CHP. The number of adverse event reports associated with Chinese Proprietary Medicine, other complementary medicine and health supplements are presented. Eight hundred and ninety three adverse event reports associated with CHP in the 7-year period have been successfully collated and analyzed. In agreement with other studies, adverse events related to the "skin and appendages disorders" were the most commonly reported. Most of the cases involved dermal allergies (e.g., rashes) associated with the use of glucosamine products and most of the adulterated products were associated with the illegal addition of undeclared drugs for pain relief. Dexamethasone, chlorpheniramine, and piroxicam were the most common adulterants detected. Reporting suspected adverse events is strongly encouraged even if the causality is not confirmed because any signs of clustering will allow rapid regulatory actions to be taken. The findings from this study help to create greater awareness on the health risks, albeit low, when consuming CHP and dispelling the common misconception that "natural" means "safe." In particular, healthcare professionals and the general public should be aware of potential adulteration of CHP. The analysis of spontaneously reported adverse events is an important surveillance system in monitoring the safety of CHP and helps in the understanding of the risk associated with the use of such products. Greater collaboration and communication between healthcare professionals, regulators, patients, manufacturers, researchers, and the general public are important to ensure the quality and safety of CHP.

Is the clinical relevance of drug-food and drug-herb interactions limited to grapefruit juice and Saint-John's Wort?

An interaction of drug with food, herbs, and dietary supplements is usually the consequence of a physical, chemical or physiologic relationship between a drug and a product consumed as food, nutritional supplement or over-the-counter medicinal plant. The current educational review aims at reminding to the prescribing physicians that the most clinically relevant drug-food interactions may not be strictly limited to those with grapefruit juice and with the Saint John's Wort herbal extract and may be responsible for changes in drug plasma concentrations, which in turn decrease efficacy or led to sometimes life-threatening toxicity. Common situations handled in clinical practice such as aging, concomitant medications, transplant recipients, patients with cancer, malnutrition, HIV infection and those receiving enteral or parenteral feeding may be at increased risk of drug-food or drug-herb interactions. Medications with narrow therapeutic index or potential life-threatening toxicity, e.g., the non-steroidal anti-inflammatory drugs, opioid analgesics, cardiovascular medications, warfarin, anticancer drugs and immunosuppressants may be at risk of significant drug-food interactions to occur. Despite the fact that considerable effort has been achieved to increase patient' and doctor's information and ability to anticipate their occurrence and consequences in clinical practice, a thorough and detailed health history and dietary recall are essential for identifying potential problems in order to optimize patient prescriptions and drug dosing on an individual basis as well as to increase the treatment risk/benefit ratio.

In Vitro Assessment of CYP-Mediated Drug Interactions for Kinsenoside, an Antihyperlipidemic Candidate

Kinsenoside, the herb-derived medicine isolated from the plant Anoect chilus, has diverse pharmacological actions, and it is considered to be a promising antihyperlipidemic drug candidate. This study evaluates the effects of kinsenoside on CYP enzyme-mediated drug metabolism in order to predict the potential for kinsenoside-drug interactions. Kinsenoside was tested at different concentrations of 0.1, 0.3, 1, 3, 10, 30, and 100 µM in human liver microsomes. The c Cktail probe assay based on liquid chromatography-tandem mass spectrometry was conducted to measure the CYP inhibitory effect of kinsenoside. Subsequently, the metabolism profiles of amlodipine and lovastatin in human liver microsomes were analyzed following co-incubation with kinsenoside. The concentration levels of the parent drug and the major metabolites were compared with the kinsenoside-cotreated samples. The effect of kinsenoside was negligible on the enzyme activity of all the CYP isozymes tested even though CYP2A6 was slightly inhibited at higher concentrations. The drug-drug interaction assay also showed that the concomitant use of kinsenoside has a non-significant effect on the concentration of lovastatin or amlodipine, and their major metabolites. So, it was concluded that there is almost no risk of drug interaction between kinsenoside and CYP drug substrates via CYP inhibition.

Medicinal herbs and therapeutic drugs interactions

People mistakenly think that all herbs are safe, because of the fact that they are natural, and the use of herbal medication is growing. Aspects of the efficacy, safety, and quality of herbal or natural products are the subjects of on-going debates. Concurrent administration of herbs may interfere with the effect of drugs. Lack of knowledge of the interaction potential together with an underreporting of herbal use poses a challenge for health care providers and a safety concern for patients. A good understanding of the mechanisms of herb-drug interactions is also essential for assessing and minimizing clinical risks. Examples of herbal medicine-pharmaceutical drug interactions of commonly used herbs are presented. The potential pharmacokinetic and pharmacodynamic basis of such interactions is discussed, as well as the challenges associated with the identification and prediction of herb-drug interactions.

Interactions between herbs and antidiabetics: an overview of the mechanisms, evidence, importance, and management

Complementary and alternative therapies are quickly gaining importance because they are perceived to be free of side effects due to their natural origin. However, herbal remedies are complex mixtures of bioactive entities, which may interact with prescription drugs through pharmacokinetic or pharmacodynamic mechanisms and sometimes result in life-threatening consequences. In particular, diabetes patients are often treated with multiple medications due to different comorbidities, and such patients use antidiabetic medications for their entire lives; thus, it is important to make the public aware of herb interactions with antidiabetic drugs. In this paper, we summarize the reports available on the interaction of herbal remedies with oral hypoglycemic agents and describe mechanisms, preclinical or clinical evidence, importance, and management strategies.

Modulation of CYP2D6 and CYP3A4 metabolic activities by Ferula asafetida resin

Present study investigated the potential effects of Ferula asafetida resin on metabolic activities of human drug metabolizing enzymes: CYP2D6 and CYP3A4. Dextromethorphan (DEX) was used as a marker to assess metabolic activities of these enzymes, based on its CYP2D6 and CYP3A4 mediated metabolism to dextrorphan (DOR) and 3-methoxymorphinan (3-MM), respectively. In vitro study was conducted by incubating DEX with human liver microsomes and NADPH in the presence or absence of Asafetida alcoholic extract. For clinical study, healthy human volunteers received a single dose of DEX alone (phase-I) and repeated the same dose after a washout period and four-day Asafetida treatment (phase-II). Asafetida showed a concentration dependent inhibition on DOR formation (in vitro) and a 33% increase in DEX/DOR urinary metabolic ratio in clinical study. For CYP3A4, formation of 3-MM in microsomes was increased at low Asafetida concentrations (10, 25 and 50 μg/ml) but slightly inhibited at the concentration of 100 μg/ml. On the other hand, in vivo observations revealed that Asafetida significantly increased DEX/3-MM urinary metabolic ratio. The findings of this study suggest that Asafetida may have a significant effect on CYP3A4 metabolic activity. Therefore, using Ferula asafetida with CYP3A4 drug substrates should be cautioned especially those with narrow therapeutic index such as cyclosporine, tacrolimus and carbamazepine.

Synergistic interactions between the antinociceptive effect of Rhodiola rosea extract and B vitamins in the mouse formalin test

AIM

In this study, the pharmacological interactions between a Rhodiola rosea ethanol extract and B-vitamins such as thiamine (B1), riboflavine (B2), pyridoxine (B6), cyanocobalamin (B12) and a mixture of vitamins B1+B6+B12 was investigated in the mouse formalin test.

METHODS

Individual dose response curves of the Rhodiola rosea ethanol extract, as well as B-vitamins alone or in a mixture were evaluated in mice in which nociception was induced with 2% formalin intraplantarly. The antinociceptive mechanisms of the Rhodiola rosea were investigated by exploring the role of the opioid and serotonin receptors and the nitric oxide pathway. Isobolographic analysis was used to evaluate the pharmacological interactions between the Rhodiola rosea ethanol extract and each B-vitamin individually or the mixture of vitamins B1+B6+B12 by using the ED30 and a fixed 1:1 ratio combination.

RESULTS

Administration of the Rhodiola rosea extract alone or in combination with all of the vitamins produced a significant and dose-dependent antinociceptive response. The antinociceptive effect of the Rhodiola rosea extract (ED50=81 mg/kg, p.o.) was significant and reverted in the presence of antagonists of the 5-HT1A, GABA/BDZs and opioid receptors and by blocking mediators of the nitric oxide/cGMP/K(+) channels pathway. Isobolograms demonstrate that all of the combinations investigated in this study produced a synergistic interaction experimental ED30 values were significantly smaller than those calculated theoretically.

CONCLUSIONS

These results provide evidence that a Rhodiola rosea ethanol extract in combination with B-vitamins produces a significant diminution in the nociceptive response in a synergistic manner, which is controlled by various mechanisms. These findings could aid in the design of clinical studies and suggest that these combinations could be applied for pain therapy.

Pattern and predictors of complementary and alternative medicine (CAM) use among pediatric patients with epilepsy

Parents of pediatric patients with chronic conditions such as epilepsy increasingly opt for complementary and alternative medicine (CAM). However, data on the pattern and reasons of CAM use in childhood epilepsy are scarce. The objectives of this study were as follows: first, to characterize CAM use among pediatric patients with epilepsy by assessing its spectrum, prevalence, costs, and frequency of use; second, to evaluate the influence of CAM use on compliance and satisfaction with conventional care as well as to explore parent-child neurologist communication concerning CAM; and third, to investigate predictors of CAM use. A postal survey was administered to all parents of pediatric outpatients with epilepsy aged 6 to 12, who have received treatment at the neuropediatric outpatient clinic of the University Children's Hospital Heidelberg between 2007 and 2009. One hundred thirty-two of the 297 distributed questionnaires were suitable for inclusion in statistical analysis (44.7%). Forty-nine participants indicated that their children used CAM during the previous year (37.1%). Thirty different types of CAM were used, with homeopathy (55.1%), osteopathy (24.5%), and kinesiology (16.3%) being the most commonly named. A mean of 86€ (0€-500€) and 3h (1 h-30 h) per month was committed to CAM treatment. Only 53% of the users informed their child neurologist of the additional CAM treatment, while 85.6% of all parents wished to discuss CAM options with their child neurologist. Seventy-five percent of users considered the CAM treatment effective. Among the participants most likely to seek CAM treatment are parents whose children show a long duration of epileptic symptoms, parents who make use of CAM treatment themselves, and parents who value a holistic and natural treatment approach. A substantial portion of pediatric patients with epilepsy receive CAM treatment. The high prevalence of use and significant level of financial and time resources spent on CAM indicate the high importance of these treatment options for parents. On the other hand, communication concerning CAM with the child neurologist is largely insufficient despite the wish to speak about CAM. Complementary and alternative medicine users' high compliance with conventional treatment and high perceived effectiveness of CAM support an integrative approach to CAM for pediatric patients with epilepsy. Our study implies that in addition to open parent-child neurologist communication, active inquiry on CAM treatments is necessary to enable informed decision making by parents and to establish the suitability of CAM treatment for the patient. Reliable predictors for CAM use, which allow for improved identification of patients with a high likelihood to receive CAM treatment, are the duration of the illness, use of CAM by the parents themselves, and the desire of the parents to receive a holistic and natural treatment for their child.

Effects of Nigella sativa and Lepidium sativum on cyclosporine pharmacokinetics

The present study was conducted to investigate the effects of Nigella sativa and Lepidium sativum on the pharmacokinetics of cyclosporine in rabbits. Two groups of animals were treated separately with Nigella sativa (200 mg/kg p.o.) or Lepidium sativum (150 mg/kg p.o.) for eight consecutive days. On the 8th day, cyclosporine (30 mg/kg p.o.) was administered to each group one hour after herbal treatment. Blood samples were withdrawn at different time intervals (0.0, 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 6.0, 8.0, 12, and 24 hrs) from marginal ear vein. Cyclosporine was analyzed using UPLC/MS method. The coadministration of Nigella sativa significantly decreased the C_max and AUC_0−∞ of cyclosporine; the change was observed by 35.5% and 55.9%, respectively (P ≤ 0.05). Lepidium sativum did not produce any significant change in C_max of cyclosporine, although its absorption was significantly delayed compared with control group. A remarkable change was observed in T_max and AUC_0−t of Lepidium sativum treated group. Our findings suggest that concurrent consumption of Nigella sativa and Lepidium sativum could alter the pharmacokinetics of cyclosporine at various levels.

Study of natural health product adverse reactions (SONAR): active surveillance of adverse events following concurrent natural health product and prescription drug use in community pharmacies

BACKGROUND

Many consumers use natural health products (NHPs) concurrently with prescription medications. As NHP-related harms are under-reported through passive surveillance, the safety of concurrent NHP-drug use remains unknown. To conduct active surveillance in participating community pharmacies to identify adverse events related to concurrent NHP-prescription drug use.

METHODOLOGY/PRINCIPAL FINDINGS

Participating pharmacists asked individuals collecting prescription medications about (i) concurrent NHP/drug use in the previous three months and (ii) experiences of adverse events. If an adverse event was identified and if the patient provided written consent, a research pharmacist conducted a guided telephone interview to gather additional information after obtaining additional verbal consent and documenting so within the interview form. Over a total of 112 pharmacy weeks, 2615 patients were screened, of which 1037 (39.7%; 95% CI: 37.8% to 41.5%) reported concurrent NHP and prescription medication use. A total of 77 patients reported a possible AE (2.94%; 95% CI: 2.4% to 3.7%), which represents 7.4% of those using NHPs and prescription medications concurrently (95%CI: 6.0% to 9.2%). Of 15 patients available for an interview, 4 (26.7%: 95% CI: 4.3% to 49.0%) reported an AE that was determined to be "probably" due to NHP use.

CONCLUSIONS/SIGNIFICANCE

Active surveillance markedly improves identification and reporting of adverse events associated with concurrent NHP-drug use. Although not without challenges, active surveillance is feasible and can generate adverse event data of sufficient quality to allow for meaningful adjudication to assess potential harms.

The effect of garlic supplements and phytochemicals on the ADMET properties of drugs

INTRODUCTION

Garlic supplements have received wide public attention because of their health-beneficial effects. Although these products are considered as innocuous, several case reports and studies have shown the capacity of individual garlic phytochemicals/supplements to interfere with drug pharmacokinetics.

AREAS COVERED

This review covers recently published literature on garlic chemistry and composition, and provides a thorough review of published studies evaluating drug-garlic interactions. The authors illustrate the mechanisms underlying pharmacokinetic interactions, which could serve as important highlights in further research to explain results for drugs with narrow therapeutic indices or for drugs, utilizing multiple absorption, distribution and metabolism pathways.

EXPERT OPINION

To increase the relevance of further research on safety and efficacy of garlic supplements and phytochemicals, their composition should be addressed before conducting in vitro or in vivo research. It is also strongly recommended to characterize in vitro formulation performance to assess the rate and extent of garlic phytochemical release in order to anticipate the in vivo impact on the pharmacokinetics of concomitantly consumed drugs. The main conclusion of this review is that the impact of garlic on different stages of pharmacokinetics, especially on drug absorption and metabolism, is drug specific and dependent on the type/quality of utilized supplement.

Drug-nutrient interactions: a broad view with implications for practice

The relevance of drug?nutrient interactions in daily practice continues to grow with the widespread use of medication. Interactions can involve a single nutrient, multiple nutrients, food in general, or nutrition status. Mechanistically, drug?nutrient interactions occur because of altered intestinal transport and metabolism, or systemic distribution, metabolism and excretion, as well as additive or antagonistic effects. Optimal patient care includes identifying, evaluating, and managing these interactions. This task can be supported by a systematic approach for categorizing interactions and rating their clinical significance. This review provides such a broad framework using recent examples, as well as some classic drug?nutrient interactions. Pertinent definitions are presented, as is a suggested approach for clinicians. This important and expanding subject will benefit tremendously from further clinician involvement.

Polypharmacy and food-drug interactions among older persons: a review

Polypharmacy is generally defined as the use of 5 or more prescription medications on a regular basis. The average number of prescribed and over-the-counter medications used by community-dwelling older adults per day in the United States is 6 medications, and the number used by institutionalized older persons is 9 medications. Almost all medications affect nutriture, either directly or indirectly, and nutriture affects drug disposition and effect. This review will highlight the issues surrounding polypharmacy, food-drug interactions, and the consequences of these interactions for the older adult.

Patient counseling about herbal-drug interactions

Many people have the mistaken notion that, being natural, all herbs and foods are safe; this is not so. Very often, herbs and food may interact with medications you normally take, result in serious reactions. During the latter part of this century the practice of herbalism has become mainstream throughout the world. This is due remove to the recognition of the value of traditional medical systems in the world. Herbal medicines are mixtures of more than one active ingredient. The multitude of pharmacologically active compounds obviously increases the likelihood of interactions taking place. Hence, the likelihood of herb-drug interactions is theoretically higher than drug-drug interactions because synthetic drugs usually contain single chemical entity. Case reports and clinical studies have highlighted the existence of a number of clinically important interactions, although cause-and-effect relationships have not always been established. Herbs and drugs may interact either pharmacokinetically or pharmacodynamically. The predominant mechanism for this interaction is the inhibition of cytochrome P-450 3A4 in the small intestine; result in a significant reduction of drug presystemic metabolism. An additional mechanism is the inhibition of Pglycoprotein, a transporter that carries drug from the enterocyte back to the gut lumen, result in a further increase in the fraction of drug absorbed. Some herbal products (e.g. St. John's wort) have been shown to lower the plasma concentration (and/or the pharmacological effect) of a number of conventional drugs including cyclosporine, indinavir, irinotecan, nevirapine, oral contraceptives and digoxin. The data available so far, concerning this interaction and its clinical implications are reviewed in this article. It is likely that more information regarding such interaction would crop up in the future, awareness of which is necessary for achieving optimal drug therapy.

[A critical assessment of phytotherapy for prostate cancer]

Prostate cancer patients increasingly use complementary and alternative medicines to support the body's immune system in addition to conventional treatment to minimize morbidity associated with conventional treatment, to enhance the quality of life, and ultimately in the hope to cure cancer when conventional treatment fails. As there is a large variety of phytomedicines promoted as potential treatment for prostate cancer, the aim of this review was to differentiate between preventive and therapeutic approaches and evaluate which phytochemicals might be suited for therapy of prostate cancer. Therefore, preclinical in vitro and in vivo data as well as clinical trials with phytosubstances such as genistein, lycopene, epigallocatechin gallate, resveratrol, and mistletoe were assessed. The presented data show that at present there is no clinical evidence that phytochemicals might have a therapeutic use in prostate cancer in relation to reduction of tumor progression or improved survival. The question about an improved immune function or quality of life remains open. Potentially the use of phytochemicals could play a role in a preventive setting.

Dietary supplements and herbal medicine toxicities-when to anticipate them and how to manage them

BACKGROUND

Dietary supplements and herbal medicines are gaining popularity in many developed countries.

AIMS

Although most can be used without any problem, serious toxicities do occur.

METHODS

Problems can be anticipated when they are used for non-traditional indications, at excessive dose, for prolonged duration, or by patients who are also on multiple modern pharmaceuticals. Problems should also be anticipated when these products claim to be able to relieve symptoms rapidly or when herbs with pronounced pharmacological effects or toxic components are used.

RESULTS

Resuscitation, symptomatic and supportive care are the most important aspects of management of toxicities from these products.

CONCLUSION

This article reviews when problems with these products can be anticipated and outlines a practical approach to management.

American Academy of Pediatrics. The use of complementary and alternative medicine in pediatrics

The American Academy of Pediatrics is dedicated to optimizing the well-being of children and advancing family-centered health care. Related to these goals, the American Academy of Pediatrics recognizes the increasing use of complementary and alternative medicine in children and, as a result, the need to provide information and support for pediatricians. From 2000 to 2002, the American Academy of Pediatrics convened and charged the Task Force on Complementary and Alternative Medicine to address issues related to the use of complementary and alternative medicine in children and to develop resources to educate physicians, patients, and families. One of these resources is this report describing complementary and alternative medicine services, current levels of utilization and financial expenditures, and associated legal and ethical considerations. The subject of complementary and alternative medicine is large and diverse, and consequently, an in-depth discussion of each method of complementary and alternative medicine is beyond the scope of this report. Instead, this report will define terms; describe epidemiology; outline common types of complementary and alternative medicine therapies; review medicolegal, ethical, and research implications; review education and training for complementary and alternative medicine providers; provide resources for learning more about complementary and alternative medicine; and suggest communication strategies to use when discussing complementary and alternative medicine with patients and families.

A strategy for controlling potential interactions between natural health products and chemotherapy: a review in pediatric oncology

The high prevalence of complementary and alternative medicine use including natural health products (NHPs) in the pediatric oncology population is well established. The potential for concurrent use of NHPs with conventional chemotherapy necessitates physician awareness regarding the potential risks and benefits that might come from this coadministration. Knowledge of interactions between NHPs and chemotherapy is poorly characterized; however, an understanding of potential mechanisms of interaction by researchers and clinicians is important. Concerns regarding the use of antioxidants during chemotherapy are controversial and evidence exists to support both adherents and detractors in this debate. Our review addresses issues regarding potential interactions between NHPs and chemotherapies used in pediatric oncology from a pharmacokinetic and pharmacodynamic perspective. Examples of combinations of NHP and chemotherapies are briefly presented in addition to a strategy to avoid (or induce) a possible interaction between a NHP and chemotherapy. In conclusion, more clinical research is needed to substantiate or preclude the use of NHPs in the treatment of cancer and especially in combination with chemotherapy.

EFFECTS OF INDIVIDUAL GINSENOSIDES, GINKGOLIDES AND FLAVONOIDS ON CYP2C19 AND CYP2D6 ACTIVITY IN HUMAN LIVER MICROSOMES

1. The effects of four individual ginsenosides (Rb1, Rb2, Rc and Rd), two ginkgolides (A and B) and one flavonoid (quercetin) on CYP2C19-dependent S-mephenytoin 4 cent-hydroxylation and CYP2D6-mediated bufuralol 1 cent-hydroxylation were evaluated in human liver microsomes. 2. Increasing concentrations of each test compound were added to microsomal incubation mixtures containing a well-characterized marker substrate (S-mephenytoin for CYP2C19 or bufuralol for CYP2D6) to determine their IC(50) values (compound concentration yielding 50% inhibition of a marker enzyme activity), which were estimated by graphical inspection. 3. For CYP2C19, the IC(50) values were 46, 46 and 62 micromol/L for ginsenoside Rd, quercetin and ginsenoside Rb2, respectively, whereas only ginsenoside Rd had an IC(50) value of 57 micromol/L for CYP2D6. 4. The data suggest that the tested compounds are not likely to inhibit the metabolism of the concurrent use of a given drug whose primary route of elimination is through CYP2C19 or CYP2D6.

Evidence-based drug–herbal interactions

Due to the growing use of herbals and other dietary supplements healthcare providers and consumers need to know whether problems might arise from using these preparations in combination with conventional drugs. However, the evidence of interactions between natural products and drugs is based on known or suspected pharmacologic activity, data derived from in vitro or animal studies, or isolated case reports that frequently lack pertinent information. The usefulness of such information is questionable. More recently an increasing number of documented case reports, in vivo studies, and clinical trials have evaluated herbal-drug interactions. Results have sometimes been contradictory and more research is needed. Since there is a lack of rigorous studies that can establish the clinical significance of herb-drug interactions, an evidence-based evaluation of the current literature concerning commonly used herbal-drug interactions, as well as other dietary supplements, was conducted.

An Approach to Evaluating Drug-Nutrient Interactions

Although the significance of interactions between drugs is widely appreciated, little attention has been given to interactions between drugs and nutrients. Pharmacists are challenged to remember documented interactions involving available drugs, and they face the possibility that each newly approved therapeutic agent may be involved not only in unrecognized drug-drug interactions but in drug-nutrient interactions as well. A more consistent approach to evaluating drug-nutrient interactions is needed. The approach must be systematic in order to assess the influence of nutritional status, food, or specific nutrients on a drug's pharmacokinetics and pharmacodynamics, as well as the influence of a drug on overall nutritional status or on the status of a specific nutrient. We provide such a process, using several recently approved drugs as working examples. Risk factors and clinical relevance are described, with distinctions made between documented and potential interactions. Application of this process by the pharmacist to any drug will help increase their expertise. Furthermore, full consideration by pharmacists of all possible interactions of the drug regimens used in practice can allow for improved patient care.