Creation of a Natural Health Products Database for Assessing Safety for Patients with Chronic Kidney Disease or Renal Transplant

Abstract

Introduction: There is a lack of published safety information on the use of natural health products (NHPs) for patients with chronic kidney disease (CKD) or renal transplant. Objective: To create an online database to provide evidence-based safety recommendations for commonly used NHPs, specific to patients with CKD or renal transplant. Methods: NHPs used by CKD and transplant patients in British Columbia were identified from the records of the BC Provincial Renal Agency. For each NHP, several databases (MEDLINE, Embase, LexiNatural Products, PubMed Dietary Supplement Subset, and Natural Medicines) were searched for any information pertaining to dosage, adverse drug reactions, drug interactions, immunomodulatory effects, and pharmacokinetics in patients with renal disease. Each NHP was given 1 of 4 safety ratings: likely safe, possibly safe, possibly unsafe, and likely unsafe. An NHP was classified as "possibly unsafe" for patients with renal transplant if it had demonstrated in vitro immunomodulatory effects and/or significant interactions with transplant medications due to effects on the cytochrome P450 3A4 isozyme. Results: Of the 19 627 BC-registered patients with renal disease (as of August 2014), 4122 (21%) were using one or more NHPs. The Herbal-CKD website (www.herbalckd.com) was created in 2015 to provide information about 47 commonly used NHPs and 2 known nephrotoxins (aristolochic acid and silver). This website provides a systematic evaluation of safety information for selected NHPs for patients with CKD (both nondialysis and dialysis-dependent) and kidney transplant. The most common NHP safety classification was "possibly safe", reflecting the paucity of studies in renal populations and the availability of safety data for the general population. Limitations of the website include difficulty in interpreting and generalizing the safety literature because most NHP formulations are not standardized, and others are combination products. Conclusion: The website www.herbalckd.com provides an easy-to-use, evidence-based tool for health care professionals to assess the safety of NHPs for CKD and transplant patients.