Characterizing adverse events reported to the California Poison Control System on herbal remedies and dietary supplements: a pilot study.
OBJECTIVE
The purpose of this study was to (1) characterize the population who uses and reports adverse events to the California Poison Control System (CPCS) related to herbal remedies (HR) and dietary supplements (DS), (2) to assess whether adverse drug reactions (ADRs) occur within the usual recommended dosing, and (3) to describe the nature of adverse events.


METHODS
A retrospective search of HR and DS related calls was conducted between January 1997 and June 1998. Data collection included the demographics of callers, types of exposures, substances involved, amounts ingested and severity.


RESULTS
Of the 918 HR and DS calls received, 259 (28.2%) were drug information queries, 599 (65.3%) were exposures, and 60 (6.5%) were excluded. Exposures occurred most often in pediatric patients 324 (54.1%), but exposures resulting in ADRs occurred most often in adults at recommended doses. There were 233 ADRs, of which 67 (28.8%) occurred in children. The most common products involved in ADRs were zinc (38.2%), echinacea (7.7%), chromium picolinate (6.4%) and witch hazel (6%). Severity of ADRs required no treatment or was minor in a majority of cases, but may have contributed to hospitalization in three.


CONCLUSIONS
Children were involved in a majority of exposure calls to the CPCS involving HR and DS. Adults, however, were more likely to develop an ADR from these products due to intentional exposure. Overall, the ADRs caused by HR and DS were mild, could be managed at home and rarely resulted in a severe outcome or other sequelae. Products involved in ADRs were consistent with the most common HR and DS products used by adult U.S. consumers.
Department of Clinical Pharmacy, University of California-San Francisco, 333 California Street, Suite 420 Box 0613, San Francisco, CA 94118, USA.
Sally
S
Yang
Cathi E
CE
Dennehy
Candy
C
Tsourounis