Health: Onion & Garlic Poisoning in Cats

 The genus Allium includes onion, garlic, leek, chives, shallots, and scallions. All Allium  species and their derivatives can be poisonous to dogs and cats. Their toxic components can damage red blood cells (RBC), leading to a hemolytic anemia. In particular, cats are 2 to 3 times more susceptible to RBC damage from these components than other species. Onion toxicosis is noted in animals that consume more than 0.5% of their body weight; in a 10 lb cat, this would be 8 oz. Ingestion of smaller amounts over several days can lead to RBC damage. Notably, manufacturers often add onion powder to baby food to increase palatability; and baby food is often given to cats when they are ill to entice eating. Commonly, signs lag behind consumption by a few days – vomiting, diarrhea, loss of appetite, and dehydration may occur. Treatment is mainly supportive. Owners should restrict access to these foodstuffs. [MK]

Related articles:

Robertson J, Christopher M, Rogers Q: Heinz body formation in cats fed baby food containing onion powder, J Am Vet Med Assoc 212:1260, 1998.