Dogs that ingest 5-HTP can develop toxicosis, as indicated by the American Veterinary Medical Association. Records in the study, garnered from the National Animal Poison Control database, indicate 19 out of 21 dogs that accidentally ingested 5-HTP developed toxicosis, resulting in three deaths.
Dogs that ingest 5-HTP can quickly exhibit signs of toxicosis, including blindness, disorientation, diarrhea, fever and the inability to stand, cites the Cornell University College of Veterinary Medicine. If it is suspected that a dog has swallowed anything that is poisonous, the American Society for the Prevention of Cruelty to Animals offers a 24-hour poison-related emergency number on its website.
In humans, 5-HTP is used to treat depression, sleep disorders, premenstrual syndrome, fibromyalgia and attention deficit-hyperactivity disorder, notes WebMD.