lidocaine anesthetic

Lidocaine anesthetic is a local anesthetic injection administered before painful medical procedures to numb specific body regions. Lidocaine anesthetic prevents pain by blocking the nerves in the treatment area from sending pain signals to the brain. Lidocaine stabilizes the membrane of nerve cells (neurons) and inhibits the flux of sodium ions, preventing the conduction of nerve impulses to the brain.

Lidocaine anesthetic administration may include:

• Injections into the skin (percutaneous) to numb the treatment area
• Injections into a vein (intravenous) to numb a region of the body (only for upper and lower extremities, Bier block)
• Injections into areas around specific peripheral nerves (peripheral nerve blocks) including:
  • Dental
  • Shoulder and arm (brachial)
  • Ribs (intercostal)
  • Space adjacent to the vertebrae (paravertebral)
  • Perineum and lower vagina (pudendal)
  • Lower uterus, cervix and upper vagina (paracervical)
• Sympathetic nerve blocks including:
  • Neck, head upper arm and upper chest (cervical - stellate ganglion)
  • Mid to low back (lumbar)
• Injections into the space around the spinal canal (epidural/central nerve blocks) including:
  • Upper back (thoracic)
  • Lumbar
  • Tailbone area (caudal)

• Do not use lidocaine anesthetic in patients with known hypersensitivity to amide type of local anesthetics, or to any of the components in lidocaine anesthetic
• Some lidocaine anesthetic formulations may contain sulfites; do not use on patients with sulfite allergy
• Do not use lidocaine anesthetic solutions containing epinephrine in extremities such as ear, nose, fingers and toes; epinephrine constricts blood vessels, and reduced blood flow can cause tissue damage
• Patients with severe liver disease are at greater risk for increased blood concentration of lidocaine, because the drug is metabolized by the liver; use with caution
• Patients with bleeding or platelet disorders are at higher risk for superficial bleeding from the skin
• Use with caution in patients with history of malignant hyperthermia, a severe reaction to certain commonly used anesthetic drugs
• Significant systemic absorption may occur if injected into mucous membranes or open wounds
• Lidocaine anesthetic for nerve blocks and infiltration must be administered only by clinicians who are well versed and equipped to diagnose and manage dose-related toxicity and other acute emergencies that might arise
• While administering nerve blocks, care must be taken to avoid injecting into a blood vessel (except in Bier block for extremities)
• Infusion of lidocaine anesthetic into joints after arthroscopy or other surgical procedures is an unapproved use; cartilage loss (chondrolysis) can occur
• Cases of methemoglobinemia have been reported in association with lidocaine anesthetic use. Patients with glucose-6-phosphate dehydrogenase deficiency, congenital or idiopathic methemoglobinemia, cardiac or pulmonary compromise, infants under 6 months of age, and concurrent exposure to oxidizing agents or their metabolites are at higher risk for developing methemoglobinemia; monitor closely

Side effects of lidocaine anesthetic include:

• Irregular heart rhythms (arrhythmias)
• Slow heartbeat (bradycardia)
• Cardiovascular collapse
• Low blood pressure (hypotension)
• Heart block
• Swelling (edema)
• Shortness of breath (dyspnea)
• Respiratory depression
• Respiratory arrest
• Anxiety
• Agitation
• Confusion
• Euphoria
• Nervousness
• Psychosis
• Ringing in the ears (tinnitus)
• Visual disturbances including blurred or double vision
• Abnormal skin sensation (paresthesia)
• Sensations of heat, cold, or numbness
• Drowsiness
• Dizziness
• Disorientation
• Lightheadedness
• Slurred speech
• Tremors
• Muscle twitching
• Seizures
• Unconsciousness
• Coma
• Skin lesions
• Hives (urticaria)
• Severe allergic reactions (anaphylactoid)
• Difficulty swallowing
• Nausea
• Vomiting
• Administration effects:
  • Pain at intramuscular injection site
  • Intramuscular injection increases serum creatine kinase

This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug.

Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.

Injectable Solution

• 0.4%
• 0.5%
• 0.8%
• 1%
• 1.5%
• 2%
• 4%
• 5%

Adult

Infiltration Anesthesia

• Percutaneous: 1-60 mL of 0.5-1% solution (5-300 mg total dose)
• IV regional: 10-60 mL of 0.5% solution (50-300 mg total dose)

Peripheral Nerve Blocks

• Brachial: 15-20 mL of 1.5% solution (225-300 mg total dose)
• Dental: 1-5 mL of 2% solution (20-100 mg total dose)
• Intercostal: 3 mL of 1% solution (30 mg total dose)
• Paravertebral: 3-5 mL of 1% solution (30-50 mg total dose)
• Pudendal (each side): 10 mL of 1% solution (100 mg total dose)
• Paracervical obstetrical analgesia (each side): 10 mL of 1% solution (100 mg total dose)

Sympathetic Nerve Blocks

• Cervical (stellate ganglion): 5 mL of 1% solution (50 mg total dose)
• Lumbar: 5-10 mL of 1% solution (50-100 mg total dose)
• Central Neural Blocks/Epidural
• General: 2-3 mL/dermatome for anesthesia
• Thoracic: 20-30 mL of 1% solution (200-300 mg total dose)
• Lumbar analgesia: 25-30 mL of 1% solution (250-300 mg total dose)
• Lumbar anesthesia: 15-20 mL of 1.5% solution (225-300 mg), or 10-15 mL of 2% solution (200-300 mg total dose)

Dosing Considerations

• Use preservative-free preparations for spinal or epidural anesthesia
• May be buffered 9:1 with sodium bicarbonate, to reduce pain on injection (e.g. remove 2 mL of 1% lidocaine from 20 mL vial, and add 2 mL of sodium bicarbonate solution to vial)
• Maximum dose: 4.5 mg/kg, up to 300 mg lidocaine without epinephrine; or 7 mg/kg, up to 500 mg lidocaine with epinephrine 

Pediatric

Infiltration

• Percutaneous: 4-4.5 mg/kg maximum  
• IV regional: 3 mg/kg

• The patient’s vital signs should be constantly monitored after administration of every local anesthetic injection to prevent overdose.
• Oxygen should be administered at the first sign of change in vital signs.
• Overdose of lidocaine can cause convulsions and cardiovascular depression and appropriate supportive and symptomatic treatment should be immediately instituted.

Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.

Use of local anesthetics increases the risk of developing methemoglobinemia, a blood disorder, when concurrently exposed to certain drugs. Examples of drugs associated with methemoglobinemia include:

• Nitrates/nitrites such as nitric oxide, nitroglycerin, nitroprusside, nitrous oxide
• Other local anesthetics such as articaine, benzocaine, bupivacaine, lidocaine, mepivacaine, prilocaine, procaine, ropivacaine, tetracaine
• Antineoplastic agents such as cyclophosphamide, flutamide, hydroxyurea, ifosfamide, rasburicase
• Antibiotics such as dapsone, nitrofurantoin, para-aminosalicylic acid, sulfonamides
• Antimalarials such as chloroquine, primaquine
• Anticonvulsants such as phenobarbital, phenytoin, sodium valproate
• Other drugs including acetaminophen, metoclopramide, quinine, sulfasalazine

The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.

It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or health care provider if you have any questions about the medication.

• Lidocaine anesthetic may be acceptable for use in pregnancy.
• Lidocaine anesthetic is indicated for pain relief during labor and delivery, however, potential for toxicity exists. Local anesthetics cross the placenta when administered as epidural, pudendal, paracervical or caudal blocks; administer with caution and monitor mother, fetus and newborn closely for adverse effects.
• Lidocaine is excreted in breast milk and must be used with caution in nursing women.