Pharmacology: Lidocaine Hydrochloride or 2 (diethlamino) -2,6 acetoxylidide monohydrochloride is a potent local anesthetic which blocks the nerve impulse conduction by decreasing membrane permeability to sodium ions, thus elevating the threshold for electrical excitability and stabilizing the nerve potential.
Lidocaine Hydrochloride 2% Injection produces a more prompt, more intense, longer lasting and more extensive activity than does the same concentration of procaine hydrochloride. It has excellent powers for penetration and diffusion so that anesthesia of adequate duration is induced rapidly over a wide area. It is effective even without a vasoconstrictor and it appears to be the anesthetic of choice for use in patients sensitive to epinephrine and its congeners. As it does not contain epinephrine, Lidocaine Hydrochloride 2% Injection can be injected into appendages like the digits, outer ears, nose, and penis, without causing vasospasm, ischemia, or gangrene. Being of the aminoethylamide type, it is also the agent of choice for individuals who exhibit hypersensitivity reactions to ester type local anesthetics such as procaine.
Lidocaine Hydrochloride is metabolized chiefly in the liver and is excreted via the kidneys both as free drug and as its metabolites. The onset of action is about 3-5 minutes and duration of action is 60-90 minutes without epinephrine.
Lidocaine Hydrochloride 2% Injection is recommended for infiltrations and regional nerve block anesthesia in general surgical and dental procedures. It is also suitable for topical mucosal anesthesia during surgery or instrumentation.
For infiltration or regional anesthesia, use 0.5-2% solutions in dosage of 3.5-mg/kg-body weight in healthy individuals. Without epinephrine, total dose should not exceed 300 mg (15 mL). With epinephrine, total dose should not exceed 500 mg (25 mL).
For topical mucosal anesthesia, use 1.2% solution to be applied by means of spray, cotton pledges, or applicators.
It is difficult to recommend a maximum dose of a drug for children since this varies as a function of age and weight. The maximum dose may be computed for children of less than ten and who have a normal lean body mass and normal development, by the application of one of the standard pediatric formulas (e.g. Clark's rule or Young's rule).
Lidocaine Hydrochloride is contraindicated in patients with a known history of hypersensitivity either to local anesthetic agents of the amide type or to other components of the injectable formulation.
Resuscitative equipment and drugs, including oxygen; should be immediately available when any local anesthetic is used.
The safe use of Lidocaine in humans has not been established with respect to possible adverse effects upon fetal development. Careful consideration should be given to this fact before administering this drug to women of childbearing potential, particularly during early pregnancy.
Local anesthetic procedures should be used with caution when there is inflammation and/or sepsis in the proposed injection.
Lidocaine Hydrochloride should also be used with caution in patients with severe shock, heart shock, or other conduction disturbances.
The lowest dose that results in effective anesthesia should be used to avoid high plasma levels and serious adverse effects. Debilitated, elderly patients, acutely ill patients and children should be given reduced doses commensurate with their age and physical status.
In using this drug for infiltration or regional nerve block anesthesia, injection should always be made slowly and with frequent aspirations. Drowsiness following an injection of Lidocaine Hydrochloride is usually an early indication of high blood level of the drug and may occur following inadvertent intravascular administration or rapid absorption of Lidocaine.
Local anesthetics react with certain metals and cause release of their respective ions, which, if injected, may cause severe local irritation. Adequate precautions should be taken to avoid this type of interaction (see Re-sterilization under Cautions for Usage).
This drug is not intended for spinal or epidural anesthesia.
As with other local anesthetics, transient Central Nervous System reactions characterized by nervousness, dizziness, blurred vision, nausea, and tremors or convulsions may occur. Drowsiness merging into unconsciousness and respiratory arrest are the manifestations of toxicity. Treatment of patients consists of assuring and maintaining a patient's airway, supporting ventilation with oxygen, and assisted or controlled respiration as required. Should convulsions persist despite ventilatory therapy, small increments of anticonvulsive agents may be given intravenously. Examples of such agents include a benzodiazepine, an ultra-short acting barbiturate, or a short-acting barbiturate. Cardiovascular depression may require circulatory assistance with intravenous fluids and/or vasopressors as dictated by the clinical situation.
Re-sterilization: Lidocaine Hydrochloride 2% Injection may be re-sterilized by autoclaving at 121°C (250°F) for 20 minutes. Disinfecting agents containing heavy metals, which cause release of respective ions (mercury, zinc, copper, etc.) should not be used for skin or mucous membrane disinfection as they have been related to incidence of swelling and edema. When chemical disinfection of multi-dose vials is desired, either isopropyl alcohol (91%) or ethyl alcohol (70%) is recommended. Many commercially available brands of rubbing alcohol, as well as solutions of ethyl alcohol not USP grade contain denaturants which are injurious to rubber and therefore, should not be used. It is recommended that chemical disinfection be accomplished by wiping the vial thoroughly with cotton or gauze that has been moistened with the recommended alcohol just prior to use.
Store at temperatures not exceeding 30°C.
N01BB02 - lidocaine ; Belongs to the class of amides. Used as local anesthetics.
Inj (vial) 2% x 10 mL, 50 mL.