Lidocaine HCl: veterinary dose and monograph

At a glance

Drug class

Analgesic

Also known as

Xylocaine, Lignocaine, Lignox

Species with doses

Dogs, Cats, Cattle, Horses, Goats and Sheep

General dose range

1–4 mg/kg IV as needed (bolus) / CRI — check the species tables for the indication

Routes

IV, SC, Epidural

Last reviewed

1 October 2026

Indications

• Local infiltration / line block (skin lacerations, wound suturing)
• Regional / nerve blocks (paravertebral, retrobulbar, brachial plexus, intercostal)
• Epidural anaesthesia (sacrococcygeal in cattle, lumbosacral in dogs)
• Ventricular tachycardia / V-fib (cardiac arrest adjunct)
• Equine colic — analgesia + prokinetic CRI (1.3 mg/kg load + 0.05 mg/kg/min CRI)
• IM antibiotic dilution to reduce injection-site pain (1 % concentration)

Lidocaine HCl dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

• Ventricular tachycardia — initial bolus: Papich 5e and Plumb’s p.729 (Schwartz 2009): 2–4 mg/kg IV over a minute, repeated to a maximum of 8 mg/kg over 10 minutes. If effective, CRI 40–80 µg/kg/min (Plumb’s) or 1 mg/kg then 50–75 µg/kg/min (Papich). Alternative 4–6 mg/kg IM when not in shock.
• Multimodal analgesia CRI: Papich 5e: 2 mg/kg IV bolus then 0.05 mg/kg/min (50 µg/kg/min) for 24 h. Plumb’s p.729: 1–4 mg/kg IV bolus then 1–5 mg/kg/h (≈17–83 µg/kg/min) by pain severity (Dyson 2008); MLK mixture delivers lidocaine at about 40 µg/kg/min (Shaffran 2009).
• Local infiltration: Ceiling dose (not a target): up to about 6 mg/kg without adrenaline — a general anaesthesia-text limit; Papich 5e and Plumb’s (edition used) give no local-infiltration maximum. Aspirate before injecting; dilute 2% to 1% for larger fields; many products contain adrenaline (avoid in arrhythmic patients — Papich).
• Epidural analgesia: Papich 5e: 4.4 mg/kg of 2% solution. Plumb’s p.729 (Valverde 2008): 4–5 mg/kg epidurally; onset under 10 min, duration about 1.5 h; may be combined with an alpha-2 agonist or opioid.

Cats

• Ventricular arrhythmia (cautious): Papich 5e: start 0.1–0.4 mg/kg IV, increasing to 0.25–0.75 mg/kg slowly if no response. Plumb’s p.729: 0.25–0.5 mg/kg slowly IV, repeat 0.15–0.25 mg/kg in 5–20 min (Ware 2000). Cats are very sensitive to CNS toxicity and cardiodepression — monitor closely.
• Local infiltration: Ceiling dose (not a target): keep the total under about 2 mg/kg — cats are more susceptible to lidocaine toxicity (Papich 5e: longer half-life, slower clearance). This limit is general anaesthesia guidance; Papich 5e and Plumb’s give no local-infiltration dose. Dilute for accuracy.
• Ventricular arrhythmia — CRI: Papich 5e: load 0.5–1 mg/kg IV, then 10–20 µg/kg/min (0.6–1.2 mg/kg/h). Plumb’s p.729 (Ware 2000): 10–20 µg/kg/min after an effective bolus.
• Epidural analgesia: Papich 5e: 4.4 mg/kg of 2% solution. Plumb’s p.729 (Valverde 2008): 4–5 mg/kg epidurally, duration about 1.5 h.

Cattle

• Paravertebral / sacrococcygeal epidural: Standard technique: sacrococcygeal epidural 5–7 mL of 2% in an adult cow; paravertebral 4–6 mL per site at T13, L1 and L2. Plumb’s 10e pp.754–755 (label dosage, not FDA-approved): lidocaine 2% — epidural 5–15 mL; nerve block 5–20 mL; infiltration diluted to 0.5% (1 mL of 2% + 3 mL sterile water). Extra-label: local anaesthesia 3 mg/kg infiltrated SC; caudal epidural 0.22–0.5 mg/kg. Follow the local label withdrawal.
• Caudal epidural (per kg — Plumb’s 10e): Plumb’s 10e p.755 (extra-label): caudal epidural anaesthesia and analgesia 0.22–0.5 mg/kg. Obtain a FARAD withdrawal.
• Local infiltration (per kg — Plumb’s 10e): Plumb’s 10e p.755 (extra-label): local anaesthesia 3 mg/kg infiltrated subcutaneously. Obtain a FARAD withdrawal.

Horses

• Colic CRI — analgesia + prokinetic: Papich 5e: post-operative ileus 1.3 mg/kg IV bolus over 15 min, then 0.05 mg/kg/min (50 µg/kg/min) CRI. Plumb’s p.729: same regimen for 24 h (Malone 1999); colic 1.4 mg/kg IV then 0.03–0.05 mg/kg/min (Hallowell 2008).
• Ventricular arrhythmia: Papich 5e: start 0.25–0.5 mg/kg IV over 5–10 min, up to 1.3–1.5 mg/kg in refractory cases, then 30–50 µg/kg/min CRI. Plumb’s p.729 (Mogg 1999): 0.25–0.5 mg/kg slowly every 5–10 min to a total of 1.5 mg/kg.

Goats

• Local infiltration / horn block: Conservative ceiling: keep the total under about 4 mg/kg in goats and especially kids, which are prone to lidocaine toxicity — general anaesthesia teaching, not a reference figure. Plumb’s 10e p.755 gives 5 mg/kg for sheep/goat local anaesthesia (next row). Cornual block about 1–2 mL of 2% per side (dilute for kids). Obtain a withdrawal (FARAD).
• Local anaesthesia (Plumb’s 10e): Plumb’s 10e p.755 (sheep/goats, extra-label): local anaesthesia 5 mg/kg; analgesia lasts ≈80–100 minutes. Kids are especially prone to toxicity — calculate the total dose before infiltrating. Obtain a FARAD withdrawal.
• Paravertebral anaesthesia: Plumb’s 10e p.755 (sheep/goats, extra-label): 3 mL of 2% lidocaine infiltrated around each paravertebral nerve; adding epinephrine (5 µg/mL) extended analgesia from 65 to 95 minutes. Keep the TOTAL within the per-kg limit. Obtain a FARAD withdrawal.
• Epidural anaesthesia: Plumb’s 10e p.755 (goats, extra-label): 2.86 mg/kg epidurally — onset 3 minutes, duration 85 minutes; ataxia occurred in all goats. Obtain a FARAD withdrawal.

Sheep

• Local infiltration: Conservative ceiling: keep the total under about 4 mg/kg (general anaesthesia teaching, not a reference figure). Plumb’s 10e p.755 gives 5 mg/kg for sheep/goat local anaesthesia (next row). Obtain a withdrawal (FARAD).
• Local anaesthesia (Plumb’s 10e): Plumb’s 10e p.755 (sheep/goats, extra-label): local anaesthesia 5 mg/kg; analgesia lasts ≈80–100 minutes. Obtain a FARAD withdrawal.
• Paravertebral anaesthesia: Plumb’s 10e p.755 (sheep/goats, extra-label): 3 mL of 2% lidocaine infiltrated around each paravertebral nerve; adding epinephrine (5 µg/mL) extended analgesia from 65 to 95 minutes. Keep the TOTAL within the per-kg limit. Obtain a FARAD withdrawal.

Buffalo

No buffalo-specific doses are on file, so buffalo are dosed as cattle.

• Paravertebral / sacrococcygeal epidural: Standard technique: sacrococcygeal epidural 5–7 mL of 2% in an adult cow; paravertebral 4–6 mL per site at T13, L1 and L2. Plumb’s 10e pp.754–755 (label dosage, not FDA-approved): lidocaine 2% — epidural 5–15 mL; nerve block 5–20 mL; infiltration diluted to 0.5% (1 mL of 2% + 3 mL sterile water). Extra-label: local anaesthesia 3 mg/kg infiltrated SC; caudal epidural 0.22–0.5 mg/kg. Follow the local label withdrawal.
• Caudal epidural (per kg — Plumb’s 10e): Plumb’s 10e p.755 (extra-label): caudal epidural anaesthesia and analgesia 0.22–0.5 mg/kg. Obtain a FARAD withdrawal.
• Local infiltration (per kg — Plumb’s 10e): Plumb’s 10e p.755 (extra-label): local anaesthesia 3 mg/kg infiltrated subcutaneously. Obtain a FARAD withdrawal.

Contraindications

Hypersensitivity to amide local anaesthetics. Severe heart block / sinus arrest without pacer. CATS: very sensitive — half the dog dose; do not use lidocaine CRI for >24 h. Inadvertent IV during local block (always aspirate first). DO NOT add epinephrine for blocks of digits / ears / tail tip — vascular necrosis.

Species-specific warnings

Cats: HALF the dog dose. Local max 2 mg/kg. CRI not recommended for >24 h. Watch for tremor / seizures.

Goats: Cap at 4 mg/kg total. Dilute 2 % to 0.5 % for large infiltrative blocks (cornual block, scrotal).

Sheep: Same caution as goats — max 4 mg/kg.

Adverse effects

• CNS: drowsiness, tremor, seizures (high-dose IV)
• Cardiovascular: bradycardia, hypotension, conduction delay (high-dose IV)
• Cats: rapid onset toxicity at doses tolerated by dogs — pay attention
• Local: methaemoglobinaemia (rare, prilocaine more likely than lidocaine)

Drug interactions

• Beta-blockers / cimetidine: reduced hepatic clearance — toxicity risk
• Other antiarrhythmics (procainamide, amiodarone): additive cardiac toxicity
• Phenytoin: additive cardiodepression
• CNS depressants (benzodiazepines, opioids): additive CNS depression

Pregnancy and lactation

Generally safe at recommended doses. Crosses placenta. Widely used for caesarean section regional anaesthesia. FDA Category B (human).

Monitoring

• ECG / heart rate during IV bolus and CRI
• Plasma lidocaine concentration ideally; otherwise titrate by clinical effect
• CNS signs (tremor, agitation) — discontinue if seizures develop
• Aspirate before every local injection — confirm not intravascular

Toxicity and overdose

CATS: extremely sensitive — seizures and cardiovascular collapse at doses tolerated by dogs. Toxic dose in dogs: >10 mg/kg IV bolus → seizures, ventricular fibrillation. Treat seizures with diazepam, intubate, support ventilation, IV crystalloid. Bradycardia → atropine. Methaemoglobinaemia (rare) → methylene blue 1 mg/kg IV slowly.

Management: Stop infusion. Diazepam 0.5 mg/kg IV for seizures, propofol if refractory. Atropine for bradycardia. Vasopressor if hypotensive. Lipid emulsion (Intralipid 20 % 1.5 mL/kg IV bolus then 0.25 mL/kg/min) for severe local-anaesthetic systemic toxicity — emerging standard in human and small-animal medicine.

Clinical pearls

• Ventricular tachycardia in a dog: 2 mg/kg IV slow bolus, repeat in 5 min if needed, then CRI 50 µg/kg/min
• MLK CRI for major surgery: Morphine 3 mg + Lidocaine 60 mg + Ketamine 60 mg in 1 L LRS at 10 mL/kg/h gives multimodal analgesia
• Cattle sacrococcygeal epidural: 5–7 mL of 2 % lidocaine produces motor block of tail and perineum within 5 min — ideal for prolapse correction
• Equine colic prokinetic CRI: 1.3 mg/kg slow load + 0.05 mg/kg/min over 24 h reduces post-op ileus duration significantly
• Goats are 2–3× more sensitive than cattle — cap lidocaine dose at 4 mg/kg total
• NEVER use lidocaine-with-epinephrine for digit / ear / tail / penis blocks — vascular necrosis

Mechanism of action

Amide local anaesthetic — blocks voltage-gated sodium channels in axon membranes from the cytoplasmic side, halting action potential conduction. Class IB antiarrhythmic action via the same Na channel block at lower concentrations, with preferential block of partially depolarised (ischaemic) ventricular tissue. Hepatic metabolism (CYP1A2) makes hepatic dysfunction a dose-reduction trigger.

Formulations and products

• Lignocaine 2 % (20 mg/mL) injection
• Lignocaine 1 % (10 mg/mL) — for IM antibiotic dilution
• Lignocaine 4 % topical gel (Xylocaine Jelly) — applied topically, not measured per kg
• Lignocaine 10 % spray (oral / nasal procedure)

Storage

Vials 15–25 °C protected from light. Discard if discoloured. Topical gel: room temp.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

Other analgesics

• Dipyrone (Metamizole)
• Fentanyl
• Gabapentin
• Hydromorphone
• Methadone
• Morphine Sulfate
• Nalbuphine
• Paracetamol (Acetaminophen)

Frequently asked questions