Herbal medicaments are in common use. In general, the judicious use of carefully selected and prepared herbal medications seems to cause few adverse effects and may be beneficial. However, toxic effects of these products have been reported with increasing frequency. Infants and children may be even more susceptible to some of the adverse effects and toxicity of these products because of differences in physiology, immature metabolic enzyme systems, and dose per body weight. Although information promoting the use of herbal medicine is widespread, true evidence-based information about the efficacy and safety of herbal medications is limited. Although the most conservative approach is to recommend against use of herbal medicine until such evidence is available, some patients are not receptive to this approach. A reasonable approach for health care providers may be to follow such use closely, assist in herbal therapeutic decisions, and monitor for adverse effects and interactions. This manuscript discusses general concepts about herbal medicines, public health implications, and a framework for mechanisms of adverse effects from the use of botanicals. Adverse effects and toxicity of selected herbal products, including Chinese herbal medicines, are presented. The authors propose a risk reduction approach in which physicians actively seek information about the use of complementary or alternative medicine while taking medical histories.