Dog · Canis lupus familiaris · typical adult weight 2.00–80.00 kg
Phenytoin is dosed at 10 mg/kg IV single slow i.v. dose over 5 min in dogs, per BSAVA Small Animal Formulary 10th Ed, printed p.322 (corpus p.338) '10 mg/kg i.v. slowly'; interval corroborated by Papich Saunders Handbook 4th Ed printed p.634 (corpus p.663) 'Antiarrhythmic: ... 10 mg/kg IV over 5 min'. Phenytoin is used in dogs for Status epilepticus (alternative to diazepam), Epilepsy (historical use). Routes documented in dogs: IV, PO. A typical adult dog weighs 2.00–80.00 kg. ExoticRx lists 2 cited dose rules for Phenytoin in dogs, drawn from published veterinary references. Verify against current literature before clinical use.
US trade names: Dilantin
| Route | Dose | Frequency | Duration | Indication | Evidence | Source |
|---|---|---|---|---|---|---|
| IV | 10 mg/kg | single slow i.v. dose over 5 min | Single dose for acute seizures | Status epilepticus (alternative to diazepam) | Moderate | BSAVA Small Animal Formulary 10th Ed, printed p.322 (corpus p.338) '10 mg/kg i.v. slowly'; interval corroborated by Papich Saunders Handbook 4th Ed printed p.634 (corpus p.663) 'Antiarrhythmic: ... 10 mg/kg IV over 5 min' |
| PO | 15–40 mg/kg | q8h | Rapid hepatic metabolism limits utility | Epilepsy (historical use) | Moderate | Plumb's Veterinary Drug Handbook, 9th Ed |
Need the exact dose for your patient?
These ranges are per kg. Enter your dog's weight to get the precise dose and draw-up volume — unit and concentration math done for you.
Stabilizes neuronal membranes by blocking voltage-dependent sodium channels in their inactive state, preventing repetitive firing. Does not affect normal neuronal activity.
Hepatotoxicity in dogs with chronic use. Rapid hepatic metabolism in dogs limits usefulness. Zero-order kinetics make dosing unpredictable. Gingival hyperplasia. Generally not recommended in dogs — phenobarbital preferred.
Species-specific contraindications and adverse-reaction reports for dogs may differ from canine / feline reference data — consult the primary citations listed with each rule.
Phenytoin dose ranges in dogs, with cited source references: IV 10 mg/kg single slow i.v. dose over 5 min; PO 15–40 mg/kg q8h. Reference ranges from cited sources — verify against current literature before clinical use.
Documented routes for Phenytoin in dogs: IV, PO.
Cited course lengths for Phenytoin in dogs include: Single dose for acute seizures; Rapid hepatic metabolism limits utility. Duration depends on the indication — match it to the specific dose rule in the table above.
Phenytoin is indicated in dogs for: Status epilepticus (alternative to diazepam), Epilepsy (historical use).
These are general warnings for Phenytoin across species; consult the dog dosing table above for species-specific guidance. Hepatotoxicity in dogs with chronic use. Rapid hepatic metabolism in dogs limits usefulness. Zero-order kinetics make dosing unpredictable. Gingival hyperplasia. Generally not recommended in dogs — phenobarbital preferred.
Why a species-specific page? Phenytoin pharmacokinetics differ across species: dose ranges, intervals, and route preferences are not interchangeable. Cross-extrapolation from canine doses is unsafe in dogs — the rules above are the citations specific to this species, not generic recommendations.
Sourced from published veterinary references; awaiting credentialed clinical reviewer. See our editorial process. Reference only — not veterinary advice.