Petco Text Logo
Petco Pet Logo
  • Two Easy Ways to Start Earning Rewards!

    rewards header
    Become a member today!
    Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
    Petco Pay LogoBecome a credit card member today!

    Earn 2X Pals Rewards points at Petco
    when you use Petco Pay!

    APPLY NOW
    Learn More About Petco Pay Benefits

Diazepam for Pets: Anxiety, Seizures, & Muscle Relaxant Guide

Published on September 10, 2024
Updated on November 5, 2025
Reviewed by Petco's Veterinarian Team
Shop Related Products

Diazepam is a benzodiazepine that is used to treat anxiety. It also serves as a muscle relaxant and can be used to treat active seizures.

Summary

Used For:

Anxiety, muscle relaxation and anticonvulsant

Brands:

Valium

Species:

Dogs, cats, small mammals, rodents, rabbits, birds, horses

Other names:

Diastat

Drug type:

Anti-anxiety

Prescription required:

Yes; diazepam is a schedule IV controlled substance.

Pregnancy and lactation:

Should not be used pregnant or nursing animals. May cause birth defects.

Side effects:

Often related to drowsiness or sedation; however, paradoxical excitation and polyphagia (increased appetite) may occur

General description

Diazepam is in a class of medications called benzodiazepines and used in veterinary medicine as a sedative, muscle relaxant, anticonvulsant, appetite stimulant, and to treat anxiety.

Uses

Anxiety, muscle relaxation, and to control active seizure (not to prevent seizure activity)

How it works

Diazepam is a benzodiazepine which acts on the central nervous system to produce a calming effect. It works by enhacing the effects of gamma-aminobutyric acid (GABA), which is the main inhibitory neurotransmitter in the CNS.

Dosage

Dogs: 0.5 – 1 milligrams per kilogram rectally up to 3 times in a 24-hour period, 0.5 milligrams per kilogram nasally, 0.5 – 1 milligrams per kilogram intravenous, 0.5 – 2 milligrams per kilogram orally or 2 – 10 milligrams per dog orally three times a day. If used for phobias, it should be given 30-60 minutes before triggering event.

Because of concerns associated with oral diazepam and rare idiosyncratic hepatic failure in cats, oral use in cats is not recommended. Use an alternative oral benzodiazepine.

** Rabbits**: 0.5 – 2 milligrams per kilogram intravenous or intramuscular.

** Hamsters, Gerbils, Mice, Rats**: 3 – 5 mg/kg IM

** Guinea pigs: ** 0.5 – 3 mg/kg IM

Forms

Diazepam Oral Tablets: 2, 5, and 10 milligram sizes

Diazepam Oral Solution: 1 milligram per milliliter and 5 milligrams per milliliter

Diazepam Rectal Gel: 2.5, 10, and 20 milligrams

Diazepam Injection: 5 milligram per milliliter.

Storage information & handling

All diazepam products should be stored at room temperature protected from moisture and light.

What results can I expect?

Reduction in anxiety and active seizuress, as well as muscle relaxation

Missed Dosage

Give the dose as soon as possible. If it is almost time for the next dose, skip the missed dose, and continue with the regular schedule. Never give two doses at once.

Overdose / acute toxicity

Overdose is possible and the severity is dose dependent. Signs of overdose include ataxia, disorientation, depression, weakness, and hypothermia.

Side effects

Side effects may include, but are not limited to, the following:

  • Sedation/Drowsiness
  • Increased appetite
  • Ataxia (wobbly gait)
  • Irritability/Excitement
  • Aggression
  • Hepatic failure (cats)

Contraindications

Use with caution in animals that have or have had:

  • Benzodiazepine sensitivity
  • Hepatic or renal disease
  • Glaucoma
  • Aggressive animals
  • Debilitated or geriatric patients

Drug interactions

Consult your veterinarian before using diazepam with any other medications, even vitamins and supplements. The following may interact with diazepam:

  • Cimetidine
  • erythromycin
  • ketoconazole
  • digoxin
  • rifampin
  • amitriptyline
  • dexamethasone
  • mineral oil
  • omeprazole
  • quinidine
  • phenytoin
  • CNS depressant agents

Antacids should be administered at least 2 hours before or after diazepam.

Precaution

Diazepam should not be used in pregnant or nursing animals. May cause birth defects. Overdose is possible and the severity is dose dependent. Use in cats is controversial due to case reports of serious liver failure.

Laboratory considerations

Possible false negative urine glucose results.

Sources

Plumb’s Veterinary Drug Handbook

VIN Veterinary Drug Handbook

Manufacturer information: Genentech

Disclaimer
The information contained on this page is for educational purposes only. This medication should only be given under the advice of a veterinarian who has examined your pet under the laws applicable to your state of residence.

Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Share

Styled arrow button