Onion toxicity in pets

substance: N-propyl disulfide, sodium alkenyl thiosulfates

categories:

Fruits & Vegetables

symptoms:

Abdominal pain / Diarrhea / Hypersalivation / Tachycardia / Tachypnea / Vomiting / Weakness

# Description

Onions are a common kitchen ingredient but pose a serious risk to pets. They contain compounds that can damage pets' red blood cells, leading to a condition called hemolytic anemia. All forms of onion—raw, cooked, powdered, or even within foods—can be toxic to dogs and cats, with symptoms appearing from even a small amount. Signs of onion toxicity include weakness, vomiting, drooling, abdominal pain, pale gums, and, in severe cases, collapse.

# Toxicity

all

Safe 0-5 g/kg
Toxic 5< g/kg

# How it works

Onion contains toxic compounds like n-propyl disulfide and sodium alk(en)yl thiosulfates that cause oxidative damage to red blood cells. These compounds lead to the formation of Heinz bodies and eccentrocytes, increasing red blood cell fragility and risk of hemolysis. Oxidative damage also affects hemoglobin, resulting in impaired oxygen delivery to tissues, and inhibits enzymes crucial for red blood cell protection, further increasing susceptibility to cell damage.

# Symptoms

Gastrointestinal: Diarrhea, vomiting, abdominal pain.

Cardiovascular: Tachycardia (from anemia and methemoglobinemia), low blood pressure.

General: Heinz body anemia, methemoglobinemia.

Renal: Hemoglobin in urine, urinary casts.

Respiratory: Rapid breathing, low oxygen levels due.

# Treatment

Emesis: Induce vomiting if ingestion was within 1–2 hours and the pet is asymptomatic. Administer a single dose of activated charcoal with a cathartic.

Hospitalization and supportive care may be needed if symptoms develop. IV fluids may help with vomiting, diarrhea, hemoglobinuria, or low blood pressure, and a red blood cell transfusion may be needed for anemia.

Antiemetics:

Maropitant (1 mg/kg) once daily

Ondansetron (0.5-1 mg/kg) every 12 hours.

Antioxidants:

Vitamin C (30 mg/kg) every 6–8 hours
Vitamin E (50–600 units daily)
N-acetylcysteine.

# Prognosis

Generally favorable with timely decontamination and supportive care. A veterinary visit is essential for assessment and treatment.

Symptoms

Poisons