An article in THE LANCET this week highlights problems associated with the identification of links between dietary supplements and adverse health events.
Deleterious side-effects associated with dietary supplements are difficult to monitor in the USA because these products are not registered before sale, and although information about their content and safety does exist, it is incomplete and not readily available. Dietary supplements are a class of products that include botanicals, such as herbal remedies, non-botanicals such as minerals and vitamins, and traditional cultural remedies.
Mary Palmer from the Department of Emergency Medicine at Landspitali University Hospital, Iceland did an observational study in US poison control centres with the aim of assessing the completeness of information sources about adverse events related to dietary supplements, as well as identifying hazardous events and evaluating the effects of long-term use and multiple ingredients.
The authors noted that only 36% of 1232 dietary supplement products reported to poison control centres were listed in the commercial information database used by staff in such centres. Furthermore, fewer than half all adverse events related to dietary supplements were documented in any of the five information sources they consulted. The authors also noted that a third of observed events met criteria of hazard and that use of multiple ingredients, long-term use, and patients’ age were all associated with increased symptom severity.
Because their results show that at least some dietary supplements have potential for substantial hazard, Mary Palmer comments that “safety research should become a priority in investigations of dietary supplements to clarify hazards and possible risks”.
Dr Mary Palmer, Department of Emergency Medicine, Landspitali University Hospital – Fossvogi, 108 Reykjavik, Iceland. T) (US number) +1 571 275 5242; F) +354-543-2015; E) [email protected]
Dr Susan Smolinske, 4160 John R, Suite 616, Detroit, MI 48201; T) +1 313-745-5430; F) +1 313-745-5493; E) [email protected]
Dr Lewis Nelson, New York City Poison Control, 455 First Avenue, Room 123, New York, NY 10016; T) + 1 212 447 8150; F)
+1 212 447 8223; E) [email protected]