The U.S. Food and Drug Administration issued a safety alert on Tuesday regarding dimethylhexylamine (DMHA), a stimulant found in dozens of popular pre-workout supplements sold online and in retail stores. The alert comes after 47 adverse event reports were filed in the first quarter of 2026, including cases of elevated heart rate, chest pain, and two hospitalizations.
DMHA, which is chemically similar to the banned substance DMAA, provides an intense energy boost but carries significant cardiovascular risks, particularly when combined with caffeine. The FDA noted that many products containing DMHA do not accurately disclose the ingredient on their labels, instead listing it under proprietary blend names.
The agency is advising consumers to check supplement labels carefully and consult healthcare providers before using any pre-workout product containing stimulants beyond caffeine. Major retailers GNC and Vitamin Shoppe have voluntarily pulled several affected products from their shelves pending further review.
