Xylocaine (lidocaine hydrochloride) is a premier amide-type local anesthetic agent, representing a cornerstone in modern medical pain management. Its mechanism of action involves the reversible blockade of voltage-gated sodium channels in neuronal membranes, effectively inhibiting the initiation and conduction of nerve impulses. This results in a predictable and reliable loss of sensation in a defined area, making it indispensable for a vast array of medical, surgical, and dental procedures. Developed from a legacy of clinical research and trust, Xylocaine offers healthcare professionals a rapid-onset, intermediate-duration anesthetic with a well-characterized safety profile when administered appropriately.

Features

• Active Pharmaceutical Ingredient: Lidocaine Hydrochloride.
• Pharmacological Class: Amide Local Anesthetic.
• Multiple Formulations Available: Injectable solutions (with or without epinephrine), topical ointments, jellies, creams, and sprays.
• Rapid Onset of Action: Typically achieves anesthetic effect within 2-5 minutes for infiltration anesthesia.
• Intermediate Duration of Effect: Duration varies by formulation; plain solutions ~60-90 minutes, epinephrine-containing solutions can extend effect to ~120-240 minutes.
• Precise pH Formulation: Buffered to optimize stability and minimize injection discomfort.
• Varied Concentration Options: Ranging from 0.5% to 2% for injectables, and specific concentrations for topical applications.
• Preservative-Free Options: Available for specific clinical requirements, such as epidural administration.

Benefits

• Provides Rapid and Predictable Anesthesia: Enables clinicians to proceed with procedures quickly and efficiently, optimizing workflow and patient throughput.
• Ensures Patient Comfort and Cooperation: Effectively manages acute procedural pain, reducing patient anxiety, movement, and the stress response, leading to better procedural outcomes.
• Facilitates a Wide Range of Procedures: Its versatility makes it suitable for infiltration, nerve blocks, epidural anesthesia, and topical application across numerous medical specialties.
• Offers a Favorable Safety Profile: Decades of extensive clinical use have established a comprehensive understanding of its pharmacokinetics, pharmacodynamics, and management of potential adverse effects.
• Allows for Dose and Duration Titration: The availability of different concentrations and the option of vasoconstrictors like epinephrine provide clinicians with tools to tailor the anesthetic to the specific procedure and patient needs.

Common use

Xylocaine is indicated for the production of local anesthesia by various application techniques. Its uses are extensive and include:

• Infiltration Anesthesia: Injection directly into the tissue at the site of the intended procedure (e.g., suturing lacerations, minor surgical excisions, mole removal).
• Peripheral Nerve Blocks: Injection near a specific nerve or nerve plexus to anesthetize a larger area (e.g., brachial plexus block for arm surgery, digital block for finger procedures, dental nerve blocks).
• Central Neuraxial Blocks: Used in epidural anesthesia for labor pain management, cesarean sections, and postoperative pain control. Also used in spinal anesthesia in specific, lower-concentration formulations.
• Topical Anesthesia: Application to mucous membranes of the mouth, pharynx, larynx, trachea, urethra, and the surface of the eye for endoscopic procedures, intubation, catheterization, and tonometry.
• Intravenous Regional Anesthesia (Bier Block): Used for surgical procedures on the extremities.
• Cardiac Applications: Intravenous administration for the acute management of ventricular arrhythmias (this use is distinct from its anesthetic application).

Dosage and direction

Dosage is highly individualized and must be determined by a qualified healthcare professional based on the procedure, tissue vascularity, area to be anesthetized, patient’s physical status, and the specific formulation used. The following are general guidelines. ALWAYS CONSULT THE OFFICIAL PRESCRIBING INFORMATION.

• Maximum Recommended Dose: For healthy adults, the maximum dose for plain lidocaine (without epinephrine) is 4.5 mg/kg, not to exceed 300 mg. For lidocaine with epinephrine 1:100,000 or 1:200,000, the maximum dose is 7 mg/kg, not to exceed 500 mg. Lower maximums apply for elderly, debilitated, or pediatric patients.
• Infiltration and Nerve Blocks: Commonly used concentrations are 0.5%, 1%, and 2%. The volume injected depends on the extent of the area to be anesthetized.
• Topical Administration: Applied in a thin layer to the desired area. Dosage is based on concentration and surface area.
• Direction: Use strict aseptic technique for injections. Aspirate before injection to avoid intravascular administration. Inject slowly. For topical use, apply to intact mucosa or skin as directed.

Precautions

• Use the smallest dose and lowest concentration necessary to achieve effective anesthesia.
• Cardiovascular and Respiratory Monitoring: Resuscitative equipment and drugs (e.g., for managing convulsions and cardiac arrest) must be immediately available. Monitor vital signs continuously during major nerve blocks or other significant administrations.
• Hepatic Impairment: Use with extreme caution in patients with severe liver disease, as lidocaine is metabolized primarily in the liver. Reduced doses are typically required.
• Renal Impairment: Metabolites are excreted renally; use caution in patients with severe renal dysfunction.
• Elderly and Debilitated Patients: Often require reduced doses due to possible decreased metabolism, altered cardiac output, and increased susceptibility to side effects.
• Methaemoglobinaemia: High doses of lidocaine, particularly with prilocaine, have been associated with this condition. Use caution in patients with congenital or idiopathic methaemoglobinaemia.
• Malignant Hyperthermia: While amide local anesthetics are not known to trigger malignant hyperthermia, ensure preparedness for any hypermetabolic state.

Contraindications

• Known hypersensitivity (allergy) to lidocaine hydrochloride, other amide-type local anesthetics, or any component of the formulation.
• The use of lidocaine with vasoconstrictors (e.g., epinephrine) is contraindicated for anesthesia in areas supplied by end-arteries (e.g., digits, nose, ears, penis) or in the presence of diseases that may cause vasoconstriction and lead to necrosis (e.g., severe peripheral vascular disease, Raynaud’s syndrome, Buerger’s disease).
• Intravenous regional anesthesia (Bier Block) is contraindicated in patients with sickle cell disease or other hemoglobinopathies.
• Specific contraindications exist for epidural and spinal anesthesia (e.g., infection at the injection site, septicemia, severe hypotension, coagulopathy).

Possible side effect

Adverse reactions are generally dose-related and result from high plasma levels (often due to accidental intravascular injection or excessive dosage). Reactions can involve the Central Nervous System (CNS) and the Cardiovascular System (CVS).

• CNS Effects: Lightheadedness, dizziness, drowsiness, tinnitus, blurred or double vision, nausea, vomiting, sensations of heat or cold, twitching, tremors, convulsions, unconsciousness, and respiratory depression and arrest.
• CVS Effects: Myocardial depression leading to hypotension, bradycardia, arrhythmias, and cardiac arrest.
• Allergic Reactions: Though rare with amides, urticaria, angioedema, bronchospasm, and anaphylaxis can occur. True allergy is often to methylparaben preservative.
• Local Effects: Persistent paresthesia, pain at the injection site, and rarely, nerve damage.

Drug interaction

• Antiarrhythmics: Concurrent use with other Class I antiarrhythmic drugs (e.g., mexiletine, tocainide) may have additive cardiotoxic and neurotoxic effects.
• Beta-Blockers: Propranolol and metoprolol can decrease lidocaine metabolism, potentially leading to increased plasma levels and toxicity.
• Cimetidine: Can inhibit lidocaine metabolism, increasing the risk of adverse effects.
• Vasopressors: Drugs like ergot-type oxytocics can cause severe, persistent hypertension when combined with lidocaine solutions containing epinephrine.
• MAOIs, Tricyclic Antidepressants: Can potentiate the pressor effect of epinephrine if present in the formulation.
• Phenytoin: Additive cardiodepressant effects may occur when administered with lidocaine.

Missed dose

The concept of a “missed dose” is not applicable to Xylocaine when used as an on-demand local anesthetic for procedures. It is administered as a single dose for a specific event.

Overdose

Lidocaine overdose is a medical emergency. Management is primarily supportive.

• Symptoms: Initially CNS excitation (nervousness, dizziness, blurred vision, tinnitus, tremors, convulsions) followed by CNS depression (drowsiness, unconsciousness, respiratory arrest). CVS effects include hypotension, bradycardia, and cardiovascular collapse.
• Management:
  1. Airway: Secure and maintain a patent airway. Administer oxygen. Assist or control ventilation as needed.
  2. Convulsions: Administer a benzodiazepine (e.g., diazepam, midazolam) IV. If seizures persist, consider neuromuscular blockade with tracheal intubation and ventilation.
  3. Cardiovascular Support: Treat hypotension and bradycardia with IV fluids and vasopressors (e.g., ephedrine, norepinephrine). Treat cardiac arrest with standard Advanced Cardiac Life Support (ACLS) protocols.
  4. Circulation: Dialysis is ineffective in removing lidocaine due to its high protein binding and large volume of distribution.

Storage

• Store at controlled room temperature, 20°C to 25°C (68°F to 77°F). Avoid excessive heat (above 40°C / 104°F) and freezing.
• Protect from light. Store in the original container.
• Keep all medications out of the reach of children and pets.
• Do not use if the solution is discolored or contains particulate matter.

Disclaimer

This information is for educational and informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before undertaking any new healthcare regimen. Never disregard professional medical advice or delay in seeking it because of something you have read here. The author and publisher are not responsible for any errors or omissions or for any consequences from the application of this information.

Reviews

• “As an emergency medicine physician, Xylocaine 1% with epinephrine is my go-to for laceration repairs. Its reliability and rapid onset are unmatched. The vasoconstrictive effect is crucial for controlling bleeding in the wound bed.” – Dr. A. Chen, MD
• “In our dental practice, we rely on Xylocaine for its profound and predictable mandibular blocks. Patient comfort is excellent, and the duration is perfectly suited for most restorative procedures.” – Dr. M. Flores, DDS
• “Utilizing Xylocaine jelly for urinary catheterization in our urology clinic has dramatically improved patient tolerance for the procedure. It’s an essential part of our protocol to reduce discomfort and anxiety.” – Sarah J., RN, Urology Clinic Nurse Manager
• “The ability to use buffered lidocaine has been a game-changer for patient comfort during injection, especially in sensitive areas. It remains a cornerstone of safe and effective local anesthesia.” – Dr. R. Evans, Plastic Surgeon