Toxicity to pets

Ephedra, or ma huang, is a supplement sourced from stimulant alkaloids found in Old World (not Americas) ephedra plants. Ingestion of ephedra supplement by pet animals can cause severe clinical signs including Stomach upset, neurologica abnormalities, and heart rate changes. Wild ephedra plants that grow in the Americas (e.g., New World ephedra) contain minimal alkaloids and poisoning is not expected in pet animals following consumption; large ingestions of New World ephedra cause gastrointestinal blockage in livestock.