Oxazepam
7-chloro-3-hydroxy-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one
Also known as: Serax · oxazepamum · Wy-3498
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Fears and phobias | 0.2-0.5 mg/kg | PO | q12-24h | — | 🌎 NA |
| Fears and phobias | 0.2-1 mg/kg | PO | q12-24h | — | 🌎 NA |
| Fears and phobias | 0.2-1 mg/kg | PO | one to two times a day | — | 🌎 NA |
| Fears and phobias | 0.04-0.5 mg/kg | PO | q6h | — | 🌎 NA |
- Fears and phobias: The lowest dose and longest frequency between doses that alleviate the fear should be used.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Appetite stimulant | 2 mg per cat (total dose) | PO | every 12 hours | — | 🌎 NA |
| Appetite stimulant (hepatic lipidosis) | 0.1-0.3 mg/kg | PO | q12-24h | — | 🌎 NA |
| Appetite stimulant | 0.25-0.5 mg/kg | PO | one to two times daily | — | 🌎 NA |
| Fears and phobias | 1-2.5 mg per cat (total dose) | PO | every 12 hours | — | 🌎 NA |
| Fears and phobias | 0.2-0.5 mg/kg | PO | q12-24h | — | 🌎 NA |
| Feline urine marking | 0.2-0.5 mg/kg | PO | once to twice a day | — | 🌎 NA |
| Spraying or overgrooming | 0.2-0.5 mg/kg | PO | q12-24h | — | 🌎 NA |
| Fears and phobias | 0.2-1 mg/kg | PO | q12h or q6h | — | 🌎 NA |
- Appetite stimulant (hepatic lipidosis): If cat has a small interest in eating
- Fears and phobias: The lowest dose and longest frequency between doses that alleviate the fear should be used.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Oxazepam is a short-to-intermediate-acting benzodiazepine primarily utilized in veterinary medicine as an appetite stimulant and anxiolytic in dogs and cats.
Clinical Pearls & Pharmacologic Advantages:
- Metabolic Profile: Unlike diazepam, oxazepam does not undergo Phase I hepatic metabolism (oxidation) and lacks active metabolites. It is metabolized solely via Phase II glucuronidation.
- Geriatric & Hepatic Safety: Because of its simpler metabolic pathway, it is often considered a safer alternative to diazepam for geriatric patients or those with mild-to-moderate liver dysfunction.
- Feline Considerations: Despite its favorable metabolic profile, its use in cats with hepatic lipidosis or severe liver dysfunction remains controversial due to rare, anecdotal reports of idiosyncratic fulminant hepatic failure.
- Behavioral Use: It is used as an adjunctive oral anxiolytic for fears, phobias, and urine marking, though paradoxical excitation can occasionally occur.
Mechanism of action
Oxazepam acts as a positive allosteric modulator at the GABA-A receptor complex in the central nervous system.
- Binding: It binds to specific benzodiazepine recognition sites on the GABA-A ligand-gated chloride channel.
- Mechanism: It enhances the inhibitory effect of gamma-aminobutyric acid (GABA) by increasing the frequency of chloride channel openings.
- Pathway: Influx of chloride ions → neuronal hyperpolarization → decreased neuronal excitability.
- Clinical Effect: This depression of subcortical CNS levels (primarily limbic, thalamic, and hypothalamic) produces the characteristic anxiolytic, sedative, skeletal muscle relaxant, and anticonvulsant effects.
Safety & warnings
Contraindications
- Known benzodiazepine hypersensitivity
- Acute narrow angle glaucoma
Adverse effects
- Sedation (most common)
- Ataxia
- Paradoxical excitability, vocalization, or aggression
- Rebound anxiety or behavior worsening (if withdrawn abruptly)
- Rare precipitation of tonic-clonic seizures
- Rare idiosyncratic fulminant hepatic failure (cats)
Precautions
Important Warnings & Precautions:
- Hepatic Dysfunction: Use with caution. While less susceptible to accumulation than other benzodiazepines, rare anecdotal reports link oxazepam to fulminant hepatic failure in cats.
- Myasthenia Gravis: Benzodiazepines may exacerbate muscle weakness.
- Seizure Disorders: Use with caution in susceptible patients; rarely, it has precipitated tonic-clonic seizures.
- Pregnancy & Nursing: FDA Category D (teratogenic effects noted in animal models). Excreted in maternal milk; neonates metabolize the drug slowly, leading to potential toxic accumulation. Avoid in nursing mothers.
- Withdrawal: Avoid abrupt discontinuation to prevent rebound behavioral effects.
Drug interactions
Additive CNS depression effects may occur.
May decrease oxazepam concentrations.
May impair glucuronide conjugation (in dogs) and prolong effects.
May induce hepatic microsomal enzymes and decrease the pharmacologic effects of benzodiazepines.
May decrease oxazepam effectiveness.
May decrease oxazepam effectiveness.
Monitoring
- Clinical efficacy (improved appetite, reduced anxiety/fear)
- Adverse effects (degree of sedation, ataxia, paradoxical excitement)
Pharmacokinetics
Absorption
Absorbed from the GI tract, but is one of the more slowly absorbed oral benzodiazepines.
Distribution
Widely distributed; highly bound to plasma proteins (97% in humans). May cross the placenta and enter maternal milk.
Metabolism
Principally conjugated in the liver via glucuronidation (Phase II) to an inactive metabolite. Lacks active metabolites.
Elimination
Excreted primarily as glucuronide conjugates.
Overdose
Signs of Toxicity: When used alone, overdoses are generally limited to significant CNS depression (confusion, coma, decreased reflexes, profound sedation).
Treatment:
- Decontamination: Standard protocols for removing and/or binding the drug in the gut (e.g., emesis induction if asymptomatic and recent, activated charcoal) if taken orally.
- Supportive Care: Systemic supportive measures (IV fluids, warming, respiratory support if needed).
- Antidote: Flumazenil (a specific benzodiazepine antagonist) could potentially be used in life-threatening overdoses.
- Contraindications: The use of analeptic agents (CNS stimulants such as caffeine, amphetamines) is generally not recommended.
Available products
Formulations
- Capsules
- Tablets
Human-labeled
- Oxazepam Capsules: 10 mg, 15 mg & 30 mg (generic; Rx; C-IV)
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store oxazepam capsules and tablets at room temperature in well-closed containers.
Client information
Important: Oxazepam is a prescription medication used to stimulate appetite or reduce anxiety. It is a controlled substance.
- Timing for Appetite: If using this medication to help your pet eat, give it approximately 30 minutes before feeding for the best results.
- Do Not Stop Abruptly: If your pet has been taking this for behavior issues, do not stop the medication or change the dose without consulting your veterinarian. Sudden withdrawal can cause a "rebound" effect, making anxiety or bad behaviors worse.
- Watch for Clumsiness: The most common side effects are sleepiness and mild wobbliness (ataxia). Keep your pet away from stairs or high places until you know how the medication affects them.
- Unexpected Reactions: Rarely, some pets may have a "paradoxical" reaction where they become hyperactive, vocal, or aggressive instead of calming down. Contact your vet immediately if this happens.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.