Lidocaine + Adrenaline

Approved Indications:

• Local Anesthesia:
• Infiltration anesthesia for minor surgical procedures (e.g., dental, dermatologic, and ENT procedures).
• Nerve block anesthesia (e.g., intercostal, brachial plexus blocks).
• Field block and regional anesthesia (e.g., paravertebral, caudal, epidural).
• Prolonged Anesthesia with Hemostasis:
• Use in areas where reduced bleeding is beneficial due to the vasoconstrictive effect of adrenaline.

Clinically Accepted Off-Label Uses:

• Postoperative Pain Management:
• Local infiltration as part of multimodal pain strategies.
• Adjunct in Minor Cosmetic Surgeries:
• For its anesthetic and hemostatic properties.

Adults:

• Infiltration or Peripheral Nerve Block:
• Lidocaine 0.5–1% with Adrenaline 1:100,000 or 1:200,000.
• Maximum dose: 7 mg/kg (not exceeding 500 mg lidocaine with adrenaline).
• Epidural Anesthesia:
• 1.5% lidocaine with adrenaline 1:200,000.
• Test dose: 3 mL; then titrate as needed based on procedure.

Pediatrics:

• Dose based on weight:
• 3–5 mg/kg of lidocaine with adrenaline.
• Adjust based on age, clinical condition, and procedure.

Elderly:

• Start at lower end of dosing range; monitor for toxicity due to possible slower metabolism.

Renal/Hepatic Impairment:

• Use with caution; adjust dose as clearance of lidocaine is reduced.
• Monitor for signs of systemic toxicity.

Administration Routes:

• Subcutaneous, intradermal, infiltration, regional block, epidural (depending on formulation and use).
• Do not administer intravascularly.

Lidocaine is an amide-type local anesthetic that blocks voltage-gated sodium channels in neuronal membranes, preventing the initiation and conduction of nerve impulses, thereby inducing local anesthesia. Adrenaline (epinephrine) is a vasoconstrictor that activates α-adrenergic receptors, causing local vasoconstriction. This delays systemic absorption of lidocaine, prolongs its anesthetic effect, reduces systemic toxicity, and minimizes bleeding at the injection site.

• Absorption: Rapid when administered parenterally; slowed by adrenaline.
• Onset of Action: 1–5 minutes (depending on route and concentration).
• Duration of Action: 1–2 hours; up to 3 hours with adrenaline.
• Distribution: Crosses placenta and blood-brain barrier; volume of distribution ~0.7–2.7 L/kg.
• Metabolism: Primarily hepatic via CYP1A2 and CYP3A4 to active metabolites.
• Excretion: Renally excreted, mostly as metabolites.
• Half-life: 1.5–2 hours (prolonged in liver dysfunction).

• Pregnancy Category:
• Lidocaine: Category B (no evidence of harm in humans when used as directed).
• Adrenaline: Use with caution; systemic absorption may reduce uterine blood flow.
• Lactation:
• Lidocaine is excreted in small amounts into breast milk; generally considered safe.
• Adrenaline likely minimal in milk; caution advised but generally acceptable with close monitoring.

• Primary Class: Local Anesthetic
• Sub-Class: Amide-type local anesthetic with vasoconstrictor

• Known hypersensitivity to lidocaine, adrenaline, or other amide-type anesthetics
• Severe hypotension or shock
• Complete heart block or severe conduction disorders without pacemaker
• Local infection at the injection site
• Use in end-arterial areas (e.g., digits, nose, penis) without proper precautions due to ischemia risk

• Cardiovascular disease: Adrenaline may cause tachycardia or arrhythmias.
• Thyrotoxicosis, diabetes, or hypertension: Use adrenaline-containing solutions cautiously.
• Liver impairment: Reduced metabolism of lidocaine increases toxicity risk.
• CNS disorders (e.g., epilepsy): Lidocaine may lower seizure threshold.
• Use in End-Arterial Areas: Risk of necrosis due to vasoconstriction—avoid unless necessary and with diluted solutions.
• Clinical Monitoring: ECG, blood pressure, and signs of CNS or cardiac toxicity during procedures.

Common:

• Local pain, redness, or swelling
• Dizziness, headache
• Metallic taste, numbness of tongue or lips
• Mild tachycardia or palpitations (from adrenaline)

Serious/Rare:

• CNS toxicity: confusion, tremor, convulsions
• Cardiovascular: hypotension, bradycardia, arrhythmias, cardiac arrest
• Allergic reactions: urticaria, bronchospasm, anaphylaxis
• Tissue necrosis with improper use in digits

• Beta-blockers, MAO inhibitors, Tricyclic Antidepressants: May potentiate the cardiovascular effects of adrenaline.
• Antiarrhythmics (e.g., amiodarone): Additive effects with lidocaine.
• CYP3A4 inhibitors (e.g., erythromycin): May elevate lidocaine levels.
• Halogenated anesthetics (e.g., halothane): Increased risk of arrhythmia with adrenaline.
• Digitalis: Enhanced risk of arrhythmias when combined with adrenaline.

• Recent clinical reviews support cautious use of adrenaline-containing solutions in digits with appropriate dilution and injection technique.
• Enhanced focus on nerve-sparing techniques and lower doses for elderly or hepatic-impaired patients.
• Updated anesthesiology guidelines emphasize test dosing and aspiration before injection to avoid intravascular administration.

• Temperature: Store at 20°C to 25°C (68°F to 77°F)
• Light Protection: Store in a light-resistant container
• Humidity: Store in a dry place
• Handling: Do not freeze; shake well if instructed
• Shelf-life: Follow manufacturer’s expiry information; discard if discolored or particulate matter is visible
• Single-use ampoules or vials: Discard after opening; do not reuse