VETINUITY
Why is oral diazepam avoided in cats?
Repeated oral diazepam has caused acute fulminant hepatic necrosis in cats, often fatal, within days of starting. Injectable doses in hospital are not linked to this.
● ANSWER
Sourced & dated
What is the diazepam dose for dogs and cats?
For seizures, diazepam is dosed at 0.5 mg/kg IV in dogs and cats (repeatable up to 3 times), 0.5-2 mg/kg per rectum in dogs, or 0.1-0.5 mg/kg/h as a CRI; oral diazepam is avoided in cats.
● VETINUITY DIAZEPAM DOSE CALCULATOR
Vetinuity diazepam dose calculator
Diazepam 5 mg/mL injection. CRI row is the hourly amount.
● WHAT'S DOCUMENTED
The Vetinuity diazepam dose table for a seizing dog or cat is 0.5 mg/kg IV, repeatable up to three times, then a 0.1-0.5 mg/kg/h infusion if seizures recur; dogs without IV access can receive 0.5-2 mg/kg per rectum, the higher end for dogs on phenobarbital, and cats should not be sent home on oral diazepam. The Vetinuity diazepam dose calculator above shows milligrams and millilitres of 5 mg/mL injection for each route.
Dose table
| Indication | Dog | Cat | Route and frequency |
|---|---|---|---|
| Active seizure | 0.5 mg/kg (up to 1 mg/kg) | 0.5 mg/kg | IV, repeat every 2-5 min up to 3 doses |
| No IV access | 0.5-2 mg/kg | Use midazolam IM or intranasal instead | PR |
| Recurrent seizures | 0.1-0.5 mg/kg/h | 0.1-0.5 mg/kg/h | IV CRI |
| Co-induction | 0.2-0.4 mg/kg | 0.2-0.4 mg/kg | IV with propofol or alfaxalone |
| Appetite stimulation | Not used | Not recommended | Oral route linked to hepatic necrosis |
Handling the injection
Injectable diazepam is dissolved in propylene glycol, so it stings IM, absorbs erratically from muscle, and can cause thrombophlebitis and hypotension if pushed fast. Give it IV slowly. It binds to PVC, so infusion lines lose drug; change the bag every few hours, protect it from light, and do not mix it with other drugs in the same syringe. For IM or intranasal use, midazolam is the better benzodiazepine.
Rectal and at-home use in dogs
Podell described owners giving diazepam per rectum at home to manage cluster seizures. Dogs on phenobarbital clear diazepam faster through enzyme induction and need the higher rectal dose. Charalambous and colleagues later found intranasal midazolam controlled status epilepticus more often than rectal diazepam, which has shifted many at-home rescue plans.
Cats and the liver
Center and colleagues reported fulminant hepatic failure in cats given oral diazepam, typically within a week, most of them fatal. That is why oral diazepam is avoided in cats for appetite or behavior. Injected doses used for permethrin tremors or seizures in hospital are a separate question.
Brian Toncray, DVM, is the emergency veterinarian who built Vetinuity, and the assistant keeps this table linked to the status epilepticus protocol, propofol for refractory cases, and THC toxicity, where benzodiazepines treat agitation.
● SOURCES
- 1. Center SA, Elston TH, Rowland PH, et al. Fulminant hepatic failure associated with oral administration of diazepam in 11 cats. J Am Vet Med Assoc. 1996;209(3):618-625. PMID 8755982. Abstract. Checked 2026-10-26.
- 2. Charalambous M, Bhatti SFM, Van Ham L, et al. Intranasal Midazolam versus Rectal Diazepam for the Management of Canine Status Epilepticus: A Multicenter Randomized Parallel-Group Clinical Trial. J Vet Intern Med. 2017;31(4):1149-1158. PMID 28543780. Abstract. Checked 2026-10-26.
- 3. Podell M. The use of diazepam per rectum at home for the acute management of cluster seizures in dogs. J Vet Intern Med. 1995;9(2):68-74. PMID 7760312. Abstract. Checked 2026-10-26.
● RELATED ANSWERS
- Status Epilepticus in Dogs and Cats: Drug Doses
Vetinuity's status epilepticus table: a benzodiazepine first (midazolam 0.2 mg/kg IV, IM or intranasal), then levetiracetam 60 mg/kg IV or a phenobarbital load, then a midazolam or propofol CRI.
- Permethrin Toxicity in Cats: Methocarbamol and ILE
Control tremors with methocarbamol 55-220 mg/kg IV or diazepam 0.2-2 mg/kg IV, bathe with mild detergent and cool water, and consider 20% lipid emulsion at 1.5 mL/kg then 0.25 mL/kg/min.
- Propofol Dose for Dogs and Cats
Propofol induction is 2-4 mg/kg IV to effect in premedicated dogs (up to 6 mg/kg unpremedicated) and 2-6 mg/kg IV in cats, with a 0.1-0.4 mg/kg/min CRI for maintenance or refractory seizures.
- Alfaxalone Dose for Dogs and Cats (Alfaxan)
Alfaxalone induction is about 1-3 mg/kg IV to effect in premedicated dogs and 2-5 mg/kg IV to effect in premedicated cats, given slowly, with higher doses only in unpremedicated patients.
- Marijuana and THC Toxicity in Dogs
Suspected marijuana or THC toxicity needs veterinary assessment and supportive care, with attention to consciousness, coordination, body temperature and breathing.
● FAQ
Is intranasal midazolam better than rectal diazepam?
In a randomized multicenter trial in dogs with status epilepticus, intranasal midazolam controlled seizures more often than rectal diazepam.
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