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ELA-Max® Cream (lidocaine 4%) is a topical anesthetic cream. Lidocaine is chemically designated as acetamide, 2-(diethylamino)-N-(2,6-dimethylphenyl), has an octanol: water partition ratio of 43 at pH 7.4, and has the following structure:
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Each gram of ELA-Max Cream contains lidocaine 40 mg, lecithin, propylene glycol, benzyl alcohol, vitamin E acetate, cholesterol, carbomer 940, triethanolamine, polysorbate 80, purified water.
Mechanism of Action: ELA-Max Cream (lidocaine 4%) applied to intact skin provides dermal analgesia by a release of lidocaine from the cream into the epidermal and dermal layers of the skin, and by the accumulation of lidocaine in the vicinity of pain receptors and nerve endings. Lidocaine is an amide-type local anesthetic agent which stabilizes neuronal membranes by inhibiting the ionic fluxes required for the initiation and conduction of impulses, thereby effecting local anesthetic action. The onset, depth and duration of dermal analgesia provided by ELA-Max Cream depends primarily on the duration of application.
Dermal application of ELA-Max Cream may cause a transient, local blanching followed by a transient, local redness or erythemia.
The amount of lidocaine systemically absorbed from ELA-Max Cream is directly related to both the duration of application and to the area over which it is applied.
It is not known if lidocaine is metabolized in the skin. Lidocaine is metabolized rapidly by the liver to a number of metabolites including monoethylglycinexylidide (MEGX) and glycinexylidide (GX), both of which have pharmacologic activity similar to, but less potent than that of lidocaine. The metabolite, 2,6-xylidine, has unknown pharmacologic activity but is carcinogenic in rats (see Carcinogenesis subsection of PRECAUTIONS ).
Following intravenous administration, MEGX and GX concentrations in serum range from 11 to 36% and from 5 to 11% of lidocaine concentrations, respectively.
The half-life of lidocaine elimination from the plasma following IV administration is approximately 65 to 150 minutes (mean 110,±24 SD, n = 13). This half-life may be increased in cardiac or hepatic dysfunction. More than 98% of an absorbed dose of lidocaine can be recovered in the urine as metabolites or parent drug. The systemic clearance is 10 to 20 mL/min/kg (mean 13,±3 SD, n = 13).
ELA-Max Cream (lidocaine 4%) is indicated for the temporary relief of pain associated with minor cuts and abrasions of the skin, minor burns, including sunburn, minor skin irritation and insect bites.
ELA-Max Cream is not recommended on mucous membranes because limited studies show greater absorption of lidocaine than through intact skin. Safe dosing recommendations for use on mucous membranes cannot be made because it has not been studied adequately. ELA-Max Cream is not recommended in any clinical situation in which penetration or migration beyond the tympanic membrane into the middle ear is possible because of ototoxic effects observed in animal studies (see ).
ELA-Max Cream (lidocaine 4%) is contraindicated in patients with a known history of sensitivity to local anesthetics of the amide type or to any other component of the product.
For external use only. Avoid contact with eyes. Do not apply to irritated skin or if excessive irritation develops. If condition worsens, or if symptoms persist unaltered for more than seven days or clear up and occur again within only a few days, discontinue use of this product and consult a doctor. Do not use in large quantities, particularly over raw or blistered areas. As with any drug, if you are pregnant or nursing a baby, seek the advice of a health professional before using this product. In case of accidental ingestion, seek professional help or contact a poison control center immediately. Keep this and all medicines out of the reach of children.
Application of ELA-Max Cream to larger areas or for longer times than those recommended could result in sufficient absorption of lidocaine resulting in serious adverse effects (see DOSAGE AND ADMINISTRATION ).
Studies in laboratory animals (guinea pigs) have shown that lidocaine cream has an ototoxic effect when instilled into the middle ear. In these same studies, animals exposed to lidocaine cream in the external auditory canal only, showed no abnormality. ELA-Max Cream should not be used in any clinical situation in which its penetration or migration beyond the tympanic membrane into the middle ear is possible.
General: Repeated doses of ELA-Max Cream may increase blood levels of lidocaine. ELA-Max Cream should be used with caution in patients who may be more sensitive to the systemic effects of lidocaine including acutely ill, debilitated, or elderly patients.
ELA-Max Cream coming in contact with the eye should be avoided because animal studies have demonstrated severe eye irritation. Also the loss of protective reflexes can permit corneal irritation and potential abrasion. Absorption of lidocaine cream in conjunctival tissues has not been determined. If eye contact occurs, immediately wash out the eye with water or saline and protect the eye until sensation returns.
Patients allergic to para-aminobenzoic acid derivatives (procaine, tetracaine, benzocaine, etc.) have not shown cross sensitivity to lidocaine; however, ELA-Max Cream should be used with caution in patients with a history of drug sensitivities, especially if the etiologic agent is uncertain. Patients with severe hepatic disease, because of their inability to metabolize local anesthetics normally, are at greater risk of developing toxic plasma concentrations of lidocaine.
Information for Patients: When ELA-Max Cream is used, the patient should be aware that the production of dermal analgesia may be accompanied by the block of all sensations in the treated skin. For this reason, the patient should avoid inadvertant trauma to the treated area by scratching, rubbing, or exposure to extreme hot or cold temperatures until complete sensation has returned.
Drug Interactions: ELA-Max® Cream should be used with caution in patients receiving Class 1 antiarrhythmic drugs (such as tocainide and mexiletine) since the toxic effects are additive and generally synergistic.
Carcinogenesis: Metabolites of lidocaine have been shown to be carcinogenic in laboratory animals.
Mutagenesis The mutagenic potential of lidocaine HCl has been tested in the Ames Salmonella/mammalian microsome test and by analysis of structural chromosome aberrations in human lymphocytes in vitro , and by mouse micronucleus test in vivo . There was no indication in these tests of any mutagenic effects.
The mutagenicity of 2,6-xylidine, a metabolite of lidocaine, has been studied in different tests with mixed results. The compound was found to be weakly mutagenic in the Ames test only under metabolic activation conditions. In addition, 2,6-xylidine was observed to be mutagenic at the thymidine kinase locus, with or without activation, and induced chromosome aberrations and sister chromatid exchanges at concentrations at which the drug precipitated out of the solution (1.2 mg/mL). No evidence of genotoxicity was found in the in vivo assays measuring unscheduled DNA synthesis in rat hepatocytes, chromosome damage in polychromatic erythrocytes or preferential killing of DNA repair-deficient bacteria in liver, lung, kidney, testes and blood extracts from mice. However, covalent binding studies of DNA from liver and ethmoid turbinates in rats indicate that 2,6-xylidine may be genotoxic under certain conditions in vivo .
Impairment of Fertility: See Use in Pregnancy
Teratogenic Effects: Pregnancy Category B: There are no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, ELA-Max Cream should be used during pregnancy only if clearly needed.
Labor and Delivery: Lidocaine is not contraindicated in labor and delivery. Should ELA-Max Cream be used concomitantly with other products containing lidocaine, total doses contributed by all formulations must be considered.
Nursing Mothers: Lidocaine is excreted in human milk. Therefore, caution should be exercised when ELA-Max Cream is administered to a nursing mother since the milk: ration of lidocaine is 0.4.
Pediatric Use: Consult a doctor prior to use on children under 2 years of age. When using ELA-Max Cream in young children, care must be taken to insure that application of the cream is limited to the intended site (See DOSAGE AND ADMINISTRATION ). Accidental ingestion may lead to dose related toxicity.
Localized reactions: During or immediately after treatment with ELA-Max Cream, the skin at the site of treatment may develop erythema or edema or may be the locus of abnormal sensation.
Allergic Reactions: Allergic and anaphylactoid reactions associated with lidocaine can occur. They are characterized by urticaria, angioedema, bronchospasm, and shock. If they occur they should be managed by conventional means. The detection of sensitivity by skin testing is of doubtful value.
System (Dose Related) Reactions: Systemic adverse reactions following appropriate use of ELA-Max Cream are unlikely due to the small dose absorbed. Systemic adverse reactions of lidocaine are similar in nature to those observed with other amide local anesthetic agents including CNS excitation and/or depression (light-headedness, nervousness, apprehension, euphoria, confusion, dizziness, drowsiness, tinnitus, blurred or double vision, vomiting, sensations of heat, cold or numbness, twitching, tremors, convulsions, unconsciousness, respiratory depression and arrest). Excitatory CNS reactions may be brief or not occur at all, in which case the first manifestation may be drowsiness merging into unconsciousness. Cardiovascular manifestations may include bradycardia, hypotension, and cardiovascular collapse leading to arrest.
Peak blood levels following a 60g application to 400 cm 2 for 3 hours are 0.05 to 0.16 µg/mL for lidocaine. Toxic levels of lidocaine (>5 µg/mL) cause decreases in cardiac output, total peripheral resistance and mean arterial pressure. These changes may be attributable to direct depressant effects of these local anesthetic agents on the cardiovascular system. In the absence of massive topical overdose or oral ingestion, evaluation should include other etiologies for the clinical effects of overdosage from other sources of lidocaine or other local anesthetics.
A thick layer of ELA-Max Cream is applied to intact skin. A single application of ELA-Max Cream in a child weighing less than 10 kg should not be applied over an area larger than 100 cm 2 . A single application of ELA-Max Cream in children weighing between 10 kg and 20 kg should not be applied over an area larger than 200 cm 2 .
When applying ELA-Max Cream to young children, care must be taken to maintain careful observation of the child to prevent accidental ingestion of ELA-Max Cream.
When ELA-Max Cream (lidocaine 4%) is used concomitantly with other products containing local anesthetic agents, the amount absorbed from all formulations must be considered. The amount absorbed in the case of ELA-Max Cream is determined by the area over which it is applied and the duration of application. Although the incidence of systemic adverse reactions with ELA-Max Cream is very low, caution should be exercised, particularly when applying it over large areas and leaving it on for longer than 2 hours. The incidence of systemic adverse reactions can be expected to be directly proportional to the area and time of exposure.
ELA-Max Cream is available as the following:
Store between 15° and 30°C (59° - 86°F).
NOT FOR OPHTHALMIC USE.
KEEP CONTAINER TIGHTLY CLOSED AT ALL TIMES WHEN NOT IS USE.
Manufactured Jointly by:
Ferndale Laboratories, Inc.
Ferndale, MI 48220 and
BioZone Laboratories, Inc.
Pittsburg, CA 94565
ELA-MAX is a Registered trademark of
Ferndale Laboratories, Inc.
©Ferndale Laboratories, Inc.
MG #13350 Iss: 10/98