Liver Toxins in Cats

Because the liver is responsible for a variety of functions that are necessary for life, which include the production of the blood protein albumin, the production of bile that is necessary for digestion, and the processing of drugs and chemicals that enter the body, liver toxins can cause death if significant liver damage occurs.

Liver toxins, also known as hepatotoxins, are drugs, chemicals and other toxic substances or materials that damage the liver. Though there are many drugs that are well-known for their ability to cause liver dysfunction, the amount of damage that they cause can vary from cat to cat and depends on any pre-existing liver diseases or conditions and the way the toxic substances was metabolized by the cat's body.

Symptom severity may range from mild to severe depending on the age, breed and overall health of the cat. These symptoms include:

• Yellowing of the eyes, ears and mucous membranes (jaundice)
• Loss of appetite
• Diarrhea
• Vomiting
• Abdominal bloating due to fluids
• Tiny red or purple spots on the cat's skin (petechia)
• Larger bruise-like spots that are blue or purple-colored (ecchymosis)
• Weakness
• Lethargy
• Blood hemorrhaging
• Coma

The consumption or inhalation of drugs and toxic chemicals can damage the liver in cats. Some common drugs that are known to be hepatotoxic include phenobarbital, primidone, phenytoin, danazol, lomustine, androgenic anabolics and non-steroidal anti-inflammatory drugs (NSAIDS). Amanita mushrooms, blue-green algae, and Sago palm cycasin are also hepatotoxins that pose a risk to outdoor cats. Though cats of all ages are susceptible to liver damage from toxins, young cats are at the greatest risk due to their immature excretory functions and liver metabolism. 

To correctly identify the liver toxins that are harming the cat, it's important to bring a list of medications that the cat is taking to the veterinarian. The veterinarian will need to know the cat's health history, any prior liver conditions, when the symptoms first began, a list of symptoms, and any exposure the cat may have had to toxic substances.

The veterinarian will physically examine the cat, looking for signs of jaundice and abdominal bloating, and listening to its heart and lungs. Labs, which include a biochemical profile, a complete blood count, an electrolyte panel and a urinalysis, will be performed. The labs will indicate liver injury and will show any other organ systems that are being affected by the hepatotoxin. Lab results typically show high liver enzyme levels from liver damage, high creatinine kinase levels from damaged muscle tissue, high blood albumin levels, and protein and glucose in the urine, which is indicative of kidney damage. If the veterinarian suspects that the liver's blood clotting functions are compromised due to the damage, a blood clotting test may be ordered.

Radiographic diagnostic tools, such as X-rays and ultrasound, may also be utilized. These tests may show liver enlargement and liver damage. In order to assess the liver damage, the veterinarian may do a liver biopsy. During the liver biopsy, a small amount of tissue will be removed from the cat's liver and sent to a lab for analysis.

Blood Transfusion

If the cat's liver isn't clotting blood normally, a blood transfusion will need to occur. Either fresh whole blood or frozen plasma will be intravenously administered to the cat. Vitamin K may also be given to help blood clotting normalize and reduce the risk of internal bleeding.

Induced Vomiting and Charcoal Therapy

The veterinarian may induce vomiting to reduce the effects of ingested toxic drugs or substances. Induced vomiting must take place within 30 minutes to two hours of consumption in order to be effective. After the induced vomiting, activated charcoal will then be administered to the cat either orally or as an enema. The charcoal absorbs the excess toxins, helping to reduce their effect on the liver.

Oxygen Therapy

Oxygen will be given to the cat via a nasal cannula or a face mask. The increase of oxygen to the liver will help the liver to heal.

Fluid Therapy

Because cats with hepatotoxicity are often dehydrated as a result of vomiting and diarrhea, the cat will need to receive fluids intravenously. During fluid therapy, the veterinarian will monitor kidney function to ensure the fluids are being properly received and processed by the cat's body.

Medications

Antibiotics may be given to prevent secondary infections from occurring as a result of hepatotoxins.

Cats will need to remain in the hospital and receive intensive therapy for approximately three to 10 days. Depending on the extent of liver damage, the veterinarian may recommend a special diet for the cat to follow. The cat should be in a warm, comfortable location away from other animals and small children while it recovers from hepatotoxicity. Follow-up appointments with the veterinarian to monitor liver enzyme levels are recommended in order to keep the cat's liver functioning well. The prognosis for cats who ingest liver toxins depends on the number of toxic substances that were ingested, their effect on the liver, and how soon treatment occurred.