Dysautonomia was actually first described as a disease of horses in the United Kingdom early in the 1900's. Choke and colic were common signs caused by a lack of motility in both the esophagus and intestines. Treatment for horses with dysautonomia was non-specific, and for the most part, uniformly ineffective. Horses became acutely ill and either died or were euthanized shortly after the onset of disease. Survivors were a rarity. Local residents in the U.K. noticed that horses placed on certain pastures seemed to be at an increased risk of developing dysautonomia. This earned the disease its common name, "grass sickness". Grieg published a detailed account of the disease in a 1928 article in the Veterinary Record.

Key and Gaskell reported the first cases of feline dysautonomia at the University of Bristol in 1982. An epidemic of the disease ensued with several hundred cats being diagnosed both in the U.K. and across Europe. The number of cases peaked in the mid-1980's and has subsequently declined. As in horses, dysphagia and decreased intestinal motility are part of the clinical syndrome. In addition, cats frequently develop widely dilated, non-responsive pupils, and protrusion of the third eyelids. The prognosis is somewhat better for cats than it is for horses, but still only about 25-30% are able to survive.

Cats with dysaytonomia develop dry mucous membranes, elevated third eyelid & dilated pupils similar to dogs

Canine dysautonomia was first reported in Britain in 1983. Since then, several cases have been diagnosed across Europe and from several states in the U.S.. The first Missouri case of canine dysautonomia was diagnosed in 1988. As of January 2000, University of Missouri veterinarians and veterinary pathologists have seen a total of 42 cases.

In recent years, dysautonomia has also been reported in wild hares in the United Kingdom (1991), and in a llama in the Netherlands (1999).