Abstracts

Rationale: Patients tend not to disclose their use of herbal supplements, and fewer than 50% of adults patients in the United States discussed with their healthcare providers their herbal supplement use. Moreover, one survey showed that healthcare professionals did not ask questions of their patients about herbs and supplements use, although the healthcare professionals were aware of possible drug interactions between prescribed medications and over-the-counter medications. Methods: A 16-year-old male with generalized epilepsy maintained seizure-free status over the past two years with 1,000 mg of divalproex. Approximately two months after the initiation of an energy drink that contains multiple herbal extracts, he experienced a breakthrough seizure. The serum concentration of valproic acid showed a significant drop. The patient's parents reported that patient never missed a dose of divalproex, denied any lifestyle changes that could trigger seizures, and his body weight did not change before, during, or after the event. Results: The Drug Interaction Probability Scale for this event was 4, indicating a possible drug-herb interaction. The significant change in serum concentration of valproic acid can be associated with the initiation of energy drink. Some herbal products in the energy drink can interfere with the metabolism of valproic acid via an alteration of metabolism can inhibit absorption of valproic acid, possibly due to the inhibition of the monocarboxylate transporter. Conclusions: Considering that large adults and pediatric population in the U.S. uses dietary supplements, healthcare providers should obtain information on herbal product use, including energy drinks. Funding: None