Yerba Santa is on the FDA’s GRAS (generally regarded as safe) list for use as a food flavoring. There have been no reports of significant side effects or adverse reactions, except for the inevitable occasional allergic reaction. Nonetheless, safety in young children, pregnant or nursing women, or those with severe liver or kidney disease has not been established.
– Lawrence Review of Natural Products. Yerba santa monograph. St. Louis, MO: Facts and Comparisons, Division, J.B. Lipincott Company, 1991.
May cause diarrhea, nausea or vomiting.