1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP Injection/Solution for

What is 1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP

1% w/v Lidocaine Hydrochloride Injection USP is a sterile, aqueous solution formulated for parenteral administration. It contains 10 mg/mL of Lidocaine Hydrochloride, a commonly used local anesthetic. This preparation is presented in a 20ml glass vial and is primarily indicated for the production of local or regional anesthesia through infiltration, peripheral nerve block, or epidural techniques.

• Therapeutic Class: Amide-type local anesthetic
• Generic Name: Lidocaine Hydrochloride
• Route of Administration: Intramuscular, subcutaneous, or intravenous (with strict precautions)
• Uses: Surgical anesthesia, dental procedures, obstetric analgesia, emergency antiarrhythmic treatment

Lidocaine works by stabilizing neuronal membranes and inhibiting the ionic fluxes required for the initiation and conduction of impulses. In essence, it temporarily blocks nerve signal transmission in the area where it is applied. Because of its rapid onset and moderate duration of action, lidocaine is one of the most widely used local anesthetics in both minor and major medical procedures.

In emergency medicine, it is also administered intravenously (off-label) for the treatment of ventricular arrhythmias, particularly after myocardial infarction, though this use requires strict cardiac monitoring. Always ensure this product is administered by trained healthcare professionals under appropriate clinical settings.

How to use 1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP

The administration of 1% w/v Lidocaine Hydrochloride Injection USP should be strictly performed by trained medical personnel familiar with local and systemic anesthesia techniques. The method and dosage depend on the intended use, the patient's age, weight, and overall medical condition.

• Preparation: Inspect the vial visually for particulate matter or discoloration prior to use. Use only if the solution is clear and colorless.
• Route: Can be given via infiltration (for local anesthesia), nerve block (regional), or epidural injection. IV use is strictly for antiarrhythmic purposes under controlled settings.
• Technique:
  • Infiltration anesthesia: Inject directly into the tissue requiring anesthesia.
  • Nerve block: Inject near a specific nerve or bundle of nerves.
  • Epidural: Administer into the epidural space, especially in obstetrics.
• Dosage Safety: Always calculate the total cumulative dose to avoid toxicity. Do not exceed the maximum recommended dose of lidocaine.

After administration, patients should be monitored for signs of toxicity including CNS disturbances (dizziness, tremors, seizures) and cardiovascular symptoms (bradycardia, hypotension). Emergency resuscitative equipment and personnel should be readily available during administration. If administered intravenously (e.g., for arrhythmias), continuous ECG monitoring is essential.

Mode of Action 1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP

Lidocaine Hydrochloride acts as a local anesthetic and antiarrhythmic agent by blocking sodium channels in excitable membranes. Its primary mechanism of action is the reversible inhibition of voltage-gated sodium channels within the neuronal cell membrane.

• Primary Action: Inhibits the initiation and conduction of nerve impulses
• Target: Voltage-gated Na⁺ channels
• Effect: Local anesthesia (loss of sensation without loss of consciousness)

By preventing sodium influx during the depolarization phase of the action potential, lidocaine stops nerve signal transmission. This blockade leads to localized numbness or loss of sensation in the area supplied by the affected nerves.

When administered systemically (as in cardiac uses), lidocaine suppresses automaticity and spontaneous depolarization of the ventricles during diastole by increasing the electrical stimulation threshold of the ventricle, His-Purkinje system, and spontaneous depolarization in the ventricles.

Key characteristics:

• Onset: Rapid (within 2–5 minutes for infiltration)
• Duration: 30–60 minutes (can be prolonged with vasoconstrictors like epinephrine)
• Reversibility: Effects are temporary and dose-dependent

Lidocaine’s safety and efficacy profile make it the gold standard for short procedures requiring local or regional anesthesia. It is also favored for rapid arrhythmia suppression due to its fast onset and short half-life.

1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP Interactions 1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP

Like many pharmaceuticals, Lidocaine Hydrochloride can interact with various drugs and substances, potentially affecting efficacy or increasing the risk of side effects.

• Class I Antiarrhythmics (e.g., Mexiletine): Additive cardiac depressant effects may occur.
• Beta-blockers (e.g., Propranolol): May reduce hepatic clearance of lidocaine, increasing plasma levels and risk of toxicity.
• Cimetidine: Competitively inhibits liver enzymes and can elevate serum lidocaine levels.
• Amiodarone: Concurrent use increases the risk of cardiac depression and arrhythmias.
• Other Local Anesthetics: Potentiation of toxic effects; avoid using multiple anesthetics simultaneously.
• Phenytoin: May enhance lidocaine’s antiarrhythmic effects but also risk CNS toxicity.

Alcohol, sedatives, or CNS depressants can enhance the sedative effects of lidocaine and increase CNS side effects such as dizziness, drowsiness, and confusion.

Interactions are especially critical when lidocaine is used intravenously, as plasma concentrations influence both therapeutic and toxic responses. Therefore, drug history assessment and plasma monitoring (if available) are recommended during prolonged or high-dose use.

Dosage of 1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP

The dosage of 1% w/v Lidocaine Hydrochloride Injection USP must be individualized based on the patient’s age, weight, physical condition, and the procedure involved. Always calculate the maximum allowable dose to minimize the risk of systemic toxicity.

• Concentration: 10 mg/mL
• Maximum Single Dose (without epinephrine): 4.5 mg/kg body weight (up to 300 mg)
• Maximum Dose with epinephrine: 7 mg/kg (up to 500 mg)

Typical usage:

• Local Infiltration: 1–5 mL injected into the area of interest
• Peripheral Nerve Block: 2–10 mL depending on the nerve
• Epidural Anesthesia: 10–20 mL administered slowly into the epidural space
• IV for Antiarrhythmic Use: Loading dose of 1–1.5 mg/kg followed by infusion of 1–4 mg/min

Do not exceed recommended dosages. Cumulative dosing, especially in repeated administration, must be monitored closely. Use in children, elderly, and patients with hepatic or cardiac impairment requires reduced dosing and enhanced monitoring.

Possible side effects of 1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP

Lidocaine Injection is generally well tolerated when administered correctly. However, side effects may occur, especially if dosage exceeds the therapeutic range or if inadvertently administered intravascularly.

• Common (dose-dependent):
  • Numbness, tingling at site
  • Dizziness or lightheadedness
  • Metallic taste
  • Drowsiness
• CNS-related (signs of toxicity):
  • Restlessness, tremors
  • Seizures
  • Confusion
• Cardiovascular Effects:
  • Bradycardia
  • Hypotension
  • Cardiac arrest (in severe toxicity)
• Allergic Reactions (rare):
  • Skin rash
  • Urticaria
  • Anaphylaxis

Prompt recognition of early CNS symptoms is essential to avoid progression to severe toxicity. Emergency supportive measures including airway management, seizure control, and cardiovascular support must be readily available during administration.

1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP Contraindications 1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP

Use of Lidocaine Hydrochloride Injection is contraindicated in specific medical conditions where its administration may result in serious adverse effects.

• Known hypersensitivity to lidocaine or amide-type anesthetics
• Severe sinoatrial, AV, or intraventricular block (unless pacemaker is in place)
• Wolff-Parkinson-White (WPW) Syndrome: Risk of arrhythmias
• Severe hepatic impairment: Reduced metabolism increases toxicity risk
• Infection at injection site: Avoid local injection through infected tissue
• Porphyria: May precipitate acute attacks

Use with extreme caution in elderly patients, pregnant women, and those with cardiac, renal, or hepatic insufficiency. Thorough patient history, ECG monitoring, and liver function assessments are recommended prior to administration in high-risk individuals.

Storage of 1% w/v LIDOCAINE HYDROCHLORIDE INJECTION USP

To maintain the sterility and effectiveness of Lidocaine Hydrochloride Injection, proper storage conditions must be observed at all times.

• Storage Temperature: Store between 15°C and 30°C (59°F–86°F)
• Protect from Light: Store in a dark place or in amber-colored containers
• Do Not Freeze: Freezing may alter the stability and efficacy of the solution
• Keep in Original Packaging: Helps ensure sterility and prevent contamination

Inspect the solution before use. Discard if the solution appears discolored, cloudy, or contains particulate matter. Do not use if the vial seal is broken or tampered with.

Keep out of reach of children. Dispose of any unused product or waste material in accordance with local regulations for pharmaceutical waste. Avoid multiple uses of single-dose vials.