Bupivacaine
1-butyl-N-(2,6-dimethylphenyl)piperidine-2-carboxamide
Also known as: Sensorcaine · Marcaine · Bupivacainum · Bupivacaine hydrochloride
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 |
|---|---|---|---|---|---|
| Regional, epidural, perineural, or intrapleural analgesia | Up to 2 mg/kg | Perineural/Epidural/Intrapleural | q8h | As needed | 🌍 EU |
- Regional, epidural, perineural, or intrapleural analgesia: Unlikely to be associated with systemic side effects at this dose. Onset is 20-30 minutes for epidural; duration is 6-8 hours.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Regional, epidural, perineural, or intrapleural analgesia | Up to 2 mg/kg | Perineural/Epidural/Intrapleural | q8h | As needed | 🌍 EU |
- Regional, epidural, perineural, or intrapleural analgesia: Unlikely to be associated with systemic side effects at this dose. Cats may be more sensitive to local anaesthetic toxicity; use conservative dosing.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Bupivacaine is a potent, long-acting amide local anaesthetic used widely in veterinary medicine for regional, epidural, and perineural analgesia. It is characterized by a relatively slow onset of action compared to lidocaine but provides a significantly prolonged duration of effect (6-8 hours).
WARNING: Bupivacaine is highly cardiotoxic if administered intravenously. Extreme care must be taken to aspirate before injection to ensure the needle is not in a blood vessel.
Clinical Pearl: Small volumes of bupivacaine can be diluted with normal saline to enable wider distribution of the drug for perineural blockade. It can also be combined with lidocaine to provide both a rapid onset (from lidocaine) and prolonged duration (from bupivacaine) of sensory block while limiting the duration of motor blockade.
Mechanism of action
Bupivacaine produces reversible blockade of voltage-gated sodium channels in nerve fibres → prevents the influx of sodium required for depolarization → inhibits the propagation of action potentials → results in local anaesthesia and analgesia.
Safety & warnings
Contraindications
- Intravenous (IV) administration
- Intravenous regional anaesthesia (Bier block)
- Use of adrenaline-containing formulations at end-arterial sites (e.g., tail, digits, ears)
- Use of adrenaline-containing formulations when significant systemic absorption is likely
Adverse effects
- Severe cardiac arrhythmias (if injected intravascularly)
- Motor blockade (paresis/paralysis of affected limbs)
- CNS toxicity (seizures, tremors) at high systemic doses
- Hypotension (especially with epidural use)
Precautions
CRITICAL WARNING: Inadvertent intravascular injection may precipitate severe cardiac arrhythmias that are refractory to standard resuscitation treatments. Always aspirate prior to injection.
- Lower doses should be used when systemic absorption is likely to be high (e.g., intrapleural analgesia).
- Normal sterile precautions should be observed during administration.
Drug interactions
Additive systemic toxicity; doses must be reduced when used concurrently.
Monitoring
- Aspiration for blood prior to injection (mandatory)
- Electrocardiogram (ECG) during and after block placement
- Blood pressure
- Respiratory rate and effort (especially with epidural or intrapleural use)
- Motor function recovery
Pharmacokinetics
Half-life
Absorption
Systemic absorption depends on the site of injection, vascularity of the tissues, and presence of a vasoconstrictor (adrenaline). Intrapleural administration results in high systemic absorption.
Distribution
Highly lipid soluble and highly protein bound. Distributes widely to all tissues.
Metabolism
Hepatic metabolism via cytochrome P450 enzymes.
Elimination
Excreted primarily in the urine as metabolites.
Overdose
Overdose or inadvertent IV injection leads to profound CNS toxicity (muscle twitching, seizures, coma) and cardiovascular toxicity (profound hypotension, bradycardia, ventricular arrhythmias, asystole).
Clinical Pearl: Bupivacaine-induced cardiac arrest is notoriously resistant to standard CPR. Intravenous Lipid Emulsion (ILE) therapy (e.g., Intralipid 20%) is the specific antidote and should be administered immediately alongside standard resuscitation efforts.
Available products
Formulations
- Injectable solution: 2.5 mg/ml (0.25%)
- Injectable solution: 5.0 mg/ml (0.5%)
- Injectable solution: 7.5 mg/ml (0.75%)
- Injectable solution: 2.5 mg/ml with 1:200,000 adrenaline
- Injectable solution: 5.0 mg/ml with 1:200,000 adrenaline
Veterinary
- Marcain (POM)
- Sensorcaine (POM)
Human-labeled
- Marcain 0.25%, 0.5%, 0.75%
- Marcain Heavy (with glucose for spinal anaesthesia)
Regulatory status
Nocita (bupivacaine liposome injectable suspension) is FDA approved for dogs and cats.
POM (Prescription Only Medicine)
POM-V
No regulatory data for: 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store at room temperature (15-30°C). Do not freeze. Protect from light. Adrenaline-containing solutions are more sensitive to light and heat.
Client information
Your pet has received a long-acting local anaesthetic to control pain.
- The area treated (such as a limb) may remain numb and weak for 6 to 8 hours.
- Protect the numb area: Ensure your pet does not chew, scratch, or injure the numb limb, as they cannot feel pain in that area.
- Keep your pet confined and assist them with walking if a leg is weak to prevent falls.
- Contact your veterinarian immediately if you notice severe lethargy, muscle tremors, or difficulty breathing.
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.