NATURAL HEALTH PRODUCTS AND DRUG DISPOSITION

2005 ◽  
Vol 45 (1) ◽  
pp. 203-226 ◽  
Author(s):  
Brian C. Foster ◽  
J. Thor Arnason ◽  
Colin J. Briggs
Keyword(s):  
Health Care Professionals ◽  
Adverse Drug Events ◽  
Drug Disposition ◽  
Natural Health Products ◽  
Confounding Factors ◽  
Natural Health ◽  
Herbal Products ◽  
Health Products ◽  
History Of ◽  
Human Use

Botanicals such as herbal products (HPs) and nutraceuticals (NCs) are often regarded as low risk because of their long history of human use. Anecdotal and literature reports of adverse drug events (ADEs) and clinical studies with HPs are increasing, but many of the reports are incomplete and contradictory. These reports need to identify confounding factors and explain contradictory findings if they are to help health care professionals or patients understand what risks are involved. HPs are complex botanicals, not single-active ingredient (SAI) products. Studies can be confounded by different manufacturing processes and formulations, including cosmetics and food supplements; environment; chemotypes; misidentification or adulteration; and factors associated with the patient or user population such as use, total drug load, and genetics. Future studies need to be conducted with characterized product that includes all commercially available related products. Clinical trials should be relevant to the user population and take into account the confounding factors that may influence the interpretation of the findings.

In vitro activity of uva-ursi against cytochrome P450 isoenzymes and P-glycoproteinThis article is one of a selection of papers published in this special issue (part 2 of 2) on the Safety and Efficacy of Natural Health Products.

2007 ◽  
Vol 85 (11) ◽  
pp. 1099-1107 ◽  
Author(s):  
B. Chauhan ◽  
C. Yu ◽  
A. Krantis ◽  
I. Scott ◽  
J. T. Arnason ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Moderate Activity ◽  
Natural Health Products ◽  
Natural Health ◽  
Herbal Products ◽  
Safety And Efficacy ◽  
Methanol Extracts ◽  
Metabolism Enzymes ◽  
Health Products

Some natural health products (NHPs) affect drug metabolism enzymes and transport proteins, potentially affecting the safety and efficacy of the drug or other NHPs. This study was undertaken to characterize the effect of uva-ursi ( Arctostaphylos uva-ursi ) on cytochrome P450 isozyme (3A4, 3A5, 3A7, 2C19, and 19)-mediated metabolism and P-glycoprotein (P-gp) transport. Three bulk and 2 capsulated uva-ursi samples were obtained from commercial outlets. The capsules were batched, and herbal samples were ground to a common consistency. Aqueous and methanol extracts were freshly prepared. Cytochrome P450 isozyme-mediated metabolism was determined by using in vitro bioassays. P-gp transport function was determined by using a rhodamine 123 (Rh123) uptake test in human (THP-1) monocytes and human Caco-2 cells. All products were analyzed by HPLC for arbutin, gallic acid, myricitrin, and isoquercetin. A large variation was observed in the biomarkers found between the bulk and capsulated samples. Our data indicate that both the aqueous and methanol extracts of all 5 uva-ursi products showed high cytochrome P450 isozyme inhibition, with the exception of the methanol extracts against cytochromes P3A4 and P19, which had low to moderate activity. The aqueous extracts of uva-ursi showed an inhibitory effect on Rh123 efflux by P-gp at 1 h and an inductive effect at 18 h for both cell lines. Our results show that the uva-ursi herbal products tested here have pharmacological properties, including the potential capacity to affect drug safety and efficacy. Further studies are warranted against a wider range of cytochrome P450 isozymes and to determine whether these effects are clinically significant.

scholarly journals Interactions between Natural Health Products and Oral Anticoagulants: Spontaneous Reports in the Italian Surveillance System of Natural Health Products

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Angelica Paoletti ◽  
Eugenia Gallo ◽  
Silvia Benemei ◽  
Michele Vietri ◽  
Francesco Lapi ◽  
...  
Keyword(s):  
Natural Products ◽  
Adverse Reactions ◽  
Vitamin K Antagonists ◽  
Oral Anticoagulants ◽  
Natural Health Products ◽  
Natural Health ◽  
Herbal Products ◽  
Spontaneous Reports ◽  
Health Products ◽  
Suspected Adverse Reactions

Introduction. The safety of vitamin K antagonists (VKA) use can be compromised by many popular herbal supplements taken by individuals. The literature reports that 30% of warfarin-treated patients self-medicates with herbs. Possible interactions represent an health risk. We aimed to identify all herbs-oral anticoagulants interactions collected in the Italian database of suspected adverse reactions to “natural health” products.Methods. The Italian database of spontaneous reports of suspected adverse reactions to natural products was analyzed to address herb-VKAs interactions.Results. From 2002 to 2009, we identified 12 reports with 7 cases of INR reduction in patients treated with warfarin (n=3) and acenocoumarol (n=4), and 5 cases of INR increase (all warfarin associated). It was reported 8 different herbal products as possibly interacting.Discussion. Our study confirms the risk of interactions, highlighting the difficulty to characterize them and their mechanisms and, finally, prevent their onset. The reported data underline the urgent need of healthcare providers being aware of the possible interaction between natural products and VKA, also because of the critical clinical conditions affecting patients. This is the first step to have the best approach to understand possible INR alterations linked to herb-VKA interaction and to rightly educate patients in treatment with VKA.

scholarly journals Inhibition of Human Cytochrome P450 Metabolism by Blended Herbal Products and Vitamins

2011 ◽  
Vol 14 (1) ◽  
pp. 1 ◽  
Author(s):  
Teresa W Tam ◽  
Humayoun Akhtar ◽  
John Thor Arnason ◽  
Kosta Cvijovic ◽  
Heather Boon ◽  
...  
Keyword(s):  
Adverse Event ◽  
Cytochrome P450 ◽  
Drug Metabolism ◽  
Drug Disposition ◽  
Natural Health Products ◽  
Carotene Content ◽  
Herbal Products ◽  
Cytochrome P450 Activity ◽  
Health Products

Purpose. The use of supplements as herbal and micronutrient natural health products with conventional health products has become increasingly popular. It has been reported that some herbal products can inhibit the activity of cytochrome P450-mediated metabolism and drug disposition. This study was designed to investigate a case report of a severe adverse event to determine the potential interactions of femMED, Thyrosense and vitamins on cytochrome P450-mediated drug metabolism. Methods. The effect of extracts from these commercially available herbal formulations, trans-ß-carotene, multivitamins, and vitamin D3 supplements on cytochrome P450-mediated drug metabolism of marker substrates was determined in vitro. Results. The blended herbal products femMED and Thyrosense had a high potential to affect the safety and efficacy of many health products. Some vitamin and trans-β-carotene containing products also have the potential to affect drug disposition. The ß-carotene content of various products was analyzed and significant discrepancies were found among them and between values indicated on product labels. Product extracts also exhibited a low to moderate capacity to inhibit cytochrome P450 2C9, 2C19 and 3A4-mediated metabolism. Conclusions. The findings of this study suggest that these herbal products and most vitamin products may have an inhibitory effect on cytochrome P450 activity that could contribute to development of an adverse event. Further work is warranted to determine how supplementation with these products may affect drug metabolism in an in vivo context.

scholarly journals Current Advancements and Novel Strategies in the Treatment of Metastatic Melanoma

2021 ◽  
Vol 20 ◽  
pp. 153473542199007
Author(s):  
Siddhartha Sood ◽  
Rahul Jayachandiran ◽  
Siyaram Pandey
Keyword(s):  
Metastatic Melanoma ◽  
Complementary Therapy ◽  
Natural Health Products ◽  
Combination Therapies ◽  
Natural Health ◽  
The Past ◽  
Health Products ◽  
Melanoma Treatment ◽  
New Research

Melanoma is the deadliest form of skin cancer in the world with a growing incidence in North America. Contemporary treatments for melanoma include surgical resection, chemotherapy, and radiotherapy. However, apart from resection in early melanoma, the prognosis of patients using these treatments is typically poor. In the past decade, there have been significant advancements in melanoma therapies. Immunotherapies such as ipilimumab and targeted therapies such as vemurafenib have emerged as a promising option for patients as seen in both scientific and clinical research. Furthermore, combination therapies are starting to be administered in the form of polychemotherapy, polyimmunotherapy, and biochemotherapy, of which some have shown promising outcomes in relative efficacy and safety due to their multiple targets. Alongside these treatments, new research has been conducted into the evidence-based use of natural health products (NHPs) and natural compounds (NCs) on melanoma which may provide a long-term and non-toxic form of complementary therapy. Nevertheless, there is a limited consolidation of the research conducted in emerging melanoma treatments which may be useful for researchers and clinicians. Thus, this review attempts to evaluate the therapeutic efficacy of current advancements in metastatic melanoma treatment by surveying new research into the molecular and cellular basis of treatments along with their clinical efficacy. In addition, this review aims to elucidate novel strategies that are currently being used and have the potential to be used in the future.

Advising Cancer Patients on Natural Health Products— A Structured Approach

2004 ◽  
Vol 38 (9) ◽  
pp. 1406-1411 ◽  
Author(s):  
Mário L de Lemos ◽  
Leela John ◽  
Lynne Nakashima ◽  
Robin K O'Brien ◽  
Suzanne CM Taylor
Keyword(s):  
Cancer Patients ◽  
Natural Health Products ◽  
Natural Health ◽  
Health Products ◽  
Structured Approach

scholarly journals Molecular targets of natural health products in arthritis

2011 ◽  
Vol 13 (1) ◽  
pp. 102 ◽  
Author(s):  
Sarah Khalifé ◽  
Muhammad Zafarullah
Keyword(s):  
Molecular Targets ◽  
Natural Health Products ◽  
Natural Health ◽  
Health Products
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