Diazepam

What is this medication for?

• Status epilepticus/cluster seizures, anxiolytic, muscle relaxant, appetite stimulant (cat), preanesthetic
• Urine marking/anxiety, spraying, fast-acting anxiolytic
• Premedication/drowsiness (with ketamine); rabbit seizures

How is it given?

Give exactly as your veterinarian prescribed — never change the dose or stop on your own unless your veterinarian has told you to.

What if I miss a dose?

• Give it as soon as you remember — unless it is almost time for the next dose (then skip the missed one; never double up).
• Call your clinic if you miss more than one dose in a row.

Side effects — what should I watch for?

Effects listed as common in this handout

• Sedation, wobbliness/unsteadiness (Most common)
• Increased appetite, paradoxical CNS excitement (Especially at doses ≥0.8 mg/kg)
• Muscle fasciculations, weakness, wobbliness/unsteadiness; recumbency >0.2 mg/kg (Dose-related)

Worth a phone call to your veterinarian

• Any new symptom that worries you.

⚠️ Contact your veterinarian or an emergency clinic IMMEDIATELY if you notice

• Idiosyncratic fatal hepatic tissue death (Not dose-dependent, onset 5–11 days into oral therapy)

Before starting (or refilling), tell your veterinarian if your pet:

• has or has had: Hypersensitivity; cats exposed to chlorpyrifos (potentiates OP toxicity); significant liver disease especially in cats
• has or has had: Coma/shock/significant respiratory depression; aggressive patients (may disinhibit aggression); working dogs

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • Azole antifungals (itraconazole, ketoconazole)
  • Cimetidine, omeprazole
  • Phenobarbital, phenytoin, rifampin
  • Dexamethasone
  • Erythromycin
  • Amitriptyline, digoxin, quinidine

Storage and handling

Protect from light. Adsorbs to soft plastic (PVC) — do not store in plastic infusion bags/tubing; use glass or hard plastic (syringes) only. Insoluble in water — do not admix with aqueous fluids (precipitates).

Good to know

• Chronic oral use in cats carries a real risk of fatal idiopathic hepatic tissue death — many neurologists avoid diazepam maintenance therapy in cats altogether, preferring phenobarbital.
• Give into a vein slowly (1–3 min) — rapid injection risks low blood pressure/cardiotoxicity from the propylene glycol vehicle, especially in small animals/neonates.
• Tolerance develops with chronic dog use — not a good maintenance anticonvulsant; reserve for acute seizure emergencies.
• Do not use for zolpidem/eszopiclone toxicosis (both increase GABA activity like diazepam) — use acepromazine, chlorpromazine, or phenobarbital instead.