So many possible reasons:
1)infectious causes such as:
Viral: infectious canine hepatitis, canine herpesvirus
Bacterial: leptospirosis, liver abscess, cholangitis/cholangiohepatitis, Bartonella spp.
Fungal: histoplasmosis, coccidioidomycosis, others
Protozoal: Toxoplasma gondii, Babesia spp., Cytauxzoon felis
Rickettsial: Ehrlichia spp., Rickettsia rickettsiae
2)ingested toxins such as mushrooms,cycad palm, blue-green algae,chemicals,pesticides, aflatoxin-contaminated pet food,xylitol
3)Systemic or metabolic disorders:
Acute pancreatitis ( Are you feeding high fat diet such as lots of extra coconut oil ?)
Extrahepatic infection, septicemia, endotoxemia
Hemolytic anemia and DIC
Inflammatory bowel disease
Copper storage hepatopathy
4)hornet stings
Pasted from a vet manual:
ACUTE GENERAL TREATMENT ( of Acute Hepatic Failure )
IV fluid therapy with balanced electrolyte solution; supplement with KCI using conventional sliding scale(20-40 mEq/L to start);
maintain normoglycemia by adding 2.5%-5% dextrose to fluids. Avoid alkalosis in hepatic encephalopathy (give 0.9% saline
rather than lactated Ringer's solution).
Treat underlying cause when possible; discontinue any suspect drug; start amoxicillin or penicillin for empirical treatment of
suspected leptospirosis (dogs), or broad-spectrum systemic antibiotics for sepsis.
Give N-acetylcysteine as a glutathione source/antioxidant for treatment of acetaminophen toxicity at 140 mg/kg (10% or 20%
solution diluted at least 1:2 with saline) IV over 20-30 minutes through 0.25-m nonpyrogenic filter; then 70 mg/kg IV or PO q 6
h for 7 treatments. May also be beneficial for treatment of other drug-induced injuries (carprofen, potentiated sulfonamides,
diazepam, methimazole, others), aflatoxin-induced hepatic injury, or organic solvents and heavy metal toxicity.
Other hepatoprotective therapy (empirical therapy):
SAMe, 20 mg/kg PO q 24 h, as a glutathione source (given as follow-up to IV N-acetylcysteine when oral therapy is
tolerated)
Silybin (milk thistle) protective against Amanita mushroom toxicity in an experimental study in dogs at 50 mg/kg IV.
Oral dose for dogs and cats is 20-50 mg/kg q 24 h of 60%-80% silybin but poor absorption. Veterinary product, Marin
(Nuramax Laboratories Inc.), 5-10 mg/kg q 24 h, contains silybin bound to phosphatidylcholine to improve
gastrointestinal absorption.
Vitamin E (15 IU/kg PO q 24 h) as an antioxidant
For nonspecific control of vomiting use antiemetics such as maropitant (1 mg/kg SQ q 24 h or 2 mg/kg PO q 24 h),
metoclopramide (0.2-0.4 mg/kg IV, IM, SQ, PO q 6-8 h or 1-2 mg/kg/24 h IV constant rate infusion), or ondansetron (0.1-0.2
mg/kg SQ or slow IV q 8 h).
Treat or prevent gastric ulceration with famotidine (0.5-1 mg/kg IV or PO q 12-24 h), omeprazole (0.7-1 mg/kg PO q 12-24 h)
or pantoprazole (0.7-1 mg/kg IV q 12-24 h).
For treatment of coagulopathy, give fresh-frozen plasma and parenteral vitamin K1 (0.5-1 mg/kg q 12-24 h SQ for two or three
doses or until PT normalizes).
Treat for hepatic encephalopathy using a high-quality low-protein diet, lactulose (0.1-0.5 mL/kg PO q
12 h, adjusted to achieve soft fecal consistency), and/or intestinal antibiotics such as metronidazole (7.5-10 mg/kg PO q 12 h)
or amoxicillin-clavulanate (15 mg/kg PO q 12 h).
