Study of natural health product–drug adverse reactions (S.O.N.A.R.) in patients seeking mental health services

Abstract

Background: Natural health products (N.H.P.s) are frequently used by mental health patients, who are also more likely to be given prescription medications. Few patients report use of N.H.P.s to their health care providers, increasing the challenges of safe N.H.P. use.

Objective: To determine: (1) the proportion of patients seeking mental health services taking prescription drugs only, N.H.P.s only, prescription drug–N.H.P.s concurrently and neither, (2) which prescription drugs and N.H.P.s are most commonly used by these patients, either alone or in combination, (3) what proportion of patients in each of the above groups report an adverse event (A.E.) using active surveillance, and (4) what type of A.E.s are reported in these patient groups.

Method: Employing active surveillance, participating clinicians from six mental health clinics in Edmonton, Alberta asked individuals seeking mental health services about (i) prescription drug use, ii) N.H.P. use, and iii) experiences of A.E.s.

Results: Of 1466 patients with complete screening data available, 672 (45.8%) patients took prescription drugs only, 79 (5.4%) took N.H.P.s only, 279 (19.0%) took N.H.P.s and drugs concurrently and 436 (29.7%) took neither. In total, 147 patients reported an A.E., representing 10.7%, 2.5%, 25.5% and 0.5% of each population, respectively. Compared with prescription drug use, patients reporting concurrent N.H.P.–drug use were 2.8 times more likely to experience an A.E. (95% C.I.: 2.0–4.1; p < 0.001). A key limitation of the study is the lack of causality assessment of A.E.s reported; additionally, the patient population reflects a population that phones a provincial mental health phone line with or without referral from a mental health professional.

Conclusion: Nearly one-fifth of patients seeking mental health services take N.H.P.s and prescription drugs concurrently; these patients are also at a greater risk of experiencing an A.E. Active surveillance provides a valuable means of detecting such A.E.s and can be incorporated into the medical histories obtained by clinicians.

Keywords:

• Active surveillance
• Adverse events
• Mental health
• Natural health products
• Psychiatry

Transparency

Declaration of funding

The authors declare no funding support for the work completed in this manuscript.

Declaration of financial/other relationships

C.N., B.K., P.C., L.U., M.S., and S.V. have disclosed that they have no significant relationships with or financial interests in any commercial companies related to this study or article.

C.M.R.O. peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Acknowledgments

The authors thank Zafar Hydrie for his work as S.O.N.A.R. coordinator during the initiation of this project, Sung Hyun Kang for his contributions to data analysis and to the S.O.N.A.R. team (Heather Boon, Ross Tsuyuki, Brian Foster, Mark Ware, Theresa Charrois, Mano Murty, Rhonda Rosychuk, Don Legatt, George Cembrowski and Joanne Barnes) for their contributions and development of the original study methods and survey tools adapted for this study. We also thank June Clark for her support and contributions to this project.

Previous presentations: Pediatric Integrative Medicine Rounds, University of Alberta, Edmonton, AB, Canada, 24 February 2015; 8th Interdisciplinary Network for Complementary and Alternative Therapies for Research Symposium (I.N.-C.A.M.), Downtown Marriott, Calgary, AB, Canada, 7 November 2014; International Research Congress on Integrative Medicine and Health, Hyatt Regency, Miami, FL, USA, 15 May 2014 (poster); 17th World Congress of Basic and Clinical Pharmacology, Cape Town International Convention Centre, Cape Town, South Africa, 13–18 July 2014, (poster).