Chemocain-A

 2%+0.0005% Injection
Chemist Laboratories Ltd.

50 ml vial: ৳ 100.00

Indications

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.
Dosage & Administration

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.
Mechanism of Action (MOA)

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.

Pharmacokinetics
  • 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 & Lactation
  • 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.
Therapeutic Class
  • Primary Class: Local Anesthetic
  • Sub-Class: Amide-type local anesthetic with vasoconstrictor
Contraindications
  • 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
Warnings & Precautions
  • 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.
Side Effects

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
Drug Interactions
  • 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 Updates or Guidelines
  • 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.
Storage Conditions
  • 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
Available Brand Names