A 9 month old, female intact Labrador retriever presented to the Cornell University Hospital for Animals Emergency Service in September 2015 for known ingestion of an over-the-counter 5- HTP supplement. At-home emesis was attempted with approximately 8 ounces of hydrogen peroxide orally. Signs of agitation occurred about one hour post ingestion, and which time the patient was brought to her primary care veterinarian and subsequently referred to Cornell.