Synera

Topical Local Anesthetics

Topical Cream:
Do not apply to a procedure site after a procedure has been performed.
Wash hands before and after application.
Apply only to intact skin. Avoid application to broken or inflamed skin, the lips, or in the mouth, ears, eyes, or other areas.
Squeeze out and measure the amount of cream that approximates the amount required to achieve proper coverage using the ruler on the applicator included in the carton.
Apply the cream evenly and thinly (approximately 1 mm or the thickness of a dime) across the treatment area using a flat-surfaced tool such as a spatula or tongue depressor.
After the required application time has elapsed, remove the peel by pulling on a free edge with the fingers. Do not leave the peel on the skin for longer than recommended durations.
Dispose of used peels in such a way as to prevent accidental exposure to children or pets. Large amounts of active ingredients are contained in used peels.

Dermal patch (Synera):
Wash hands before and after application.
Remove the outer packaging immediately before the patch is applied to the skin.
Do not cut the patch, remove the top cover, or cover the holes on the top side of the patch. If the patch is cut, excess drug could be released. If the top cover is removed, the patch may generate too much heat. If the holes on the top side of the patch are covered, heat may not be generated.
Apply only to intact skin. Do not apply to broken or inflamed skin or in the mouth, ears, eyes, or to other areas.
Do not leave a patch on the skin for longer than 30 minutes. Systemic exposure of lidocaine and tetracaine is thought to be directly related to the application duration.
The patch must be removed before magnetic resonance imaging (MRI), as the integrated heating component of the patch contains iron powder.
Used patches should be folded together at the adhesive sides and disposed of in such a way as to prevent accidental exposure to children or pets.

angioedema / Rapid / Incidence not known
anaphylactoid reactions / Rapid / Incidence not known
anaphylactic shock / Rapid / Incidence not known
bronchospasm / Rapid / Incidence not known
seizures / Delayed / Incidence not known
respiratory arrest / Rapid / Incidence not known
cardiac arrest / Early / Incidence not known
arrhythmia exacerbation / Early / Incidence not known
bradycardia / Rapid / Incidence not known
coma / Early / Incidence not known
methemoglobinemia / Early / Incidence not known

erythema / Early / 47.0-71.0
edema / Delayed / 0-14.0
bullous rash / Early / 0-1.0
contact dermatitis / Delayed / 0-1.0
hypotension / Rapid / 0-1.0
dehydration / Delayed / 0-1.0
confusion / Early / 0-1.0
blurred vision / Early / Incidence not known
respiratory depression / Rapid / Incidence not known
euphoria / Early / Incidence not known

skin discoloration / Delayed / 0-16.0
acne vulgaris / Delayed / 0-1.0
vesicular rash / Delayed / 0-1.0
maculopapular rash / Early / 0-1.0
ecchymosis / Delayed / 0-1.0
rash / Early / 0-1.0
pruritus / Rapid / 0-1.0
pharyngitis / Delayed / 0-1.0
syncope / Early / 0-1.0
fever / Early / 0-1.0
paresthesias / Delayed / 0-1.0
dizziness / Early / 0-1.0
diaphoresis / Early / 0-1.0
hyperventilation / Early / 0-1.0
headache / Early / 0-1.0
pallor / Early / 0-1.0
vomiting / Early / 0-1.0
nausea / Early / 0-1.0
urticaria / Rapid / Incidence not known
anxiety / Delayed / Incidence not known
drowsiness / Early / Incidence not known
tremor / Early / Incidence not known
restlessness / Early / Incidence not known
tinnitus / Delayed / Incidence not known

Pliaglis, Synera

Rx

Local anesthetics for topical administration; available as a patch that becomes warm once the outer packaging is removed and as a cream that forms a pliable peel on the skin when exposed to air.

1 patch applied for 30 minutes before the procedure to skin lesion area. Remove the patch before the procedure. Do not leave a patch on the skin for longer than 30 minutes.

1 patch applied for 30 minutes before the procedure to skin lesion area. Remove the patch before the procedure. Do not leave a patch on the skin for longer than 30 minutes.

1 patch applied for 20 to 30 minutes before the procedure to the desired venipuncture or IV cannulation site. Remove the patch before attempting venipuncture. Do not leave a patch on the skin for longer than 30 minutes. Application of 1 additional patch to a new site to facilitate venous access after a failed attempt is acceptable.

1 patch applied for 20 to 30 minutes before the procedure to the desired venipuncture or IV cannulation site. Remove the patch before attempting venipuncture. Do not leave a patch on the skin for longer than 30 minutes. Application of 1 additional patch to a new site to facilitate venous access after a failed attempt is acceptable.

Apply an amount required to achieve proper coverage for the treatment site surface area topically to intact skin 20 to 30 minutes before the procedure. The dose of cream that provides effective local dermal analgesia depends on the duration of the application.

Apply an amount required to achieve proper coverage for the treatment site surface area topically to intact skin 60 minutes before the procedure. The dose of cream that provides effective local dermal analgesia depends on the duration of the application.

Specific dosing guidelines are not available. The half-life of lidocaine may be increased in patients with hepatic impairment.

Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.

Adapalene; Benzoyl Peroxide: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Benzalkonium Chloride; Benzocaine: (Moderate) Use tetracaine and benzocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Benzocaine: (Moderate) Use tetracaine and benzocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Benzocaine; Butamben; Tetracaine: (Moderate) Use tetracaine and benzocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Benzoyl Peroxide: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Benzoyl Peroxide; Clindamycin: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Benzoyl Peroxide; Erythromycin: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Benzoyl Peroxide; Sulfur: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Calamine; Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Chloroxylenol; Hydrocortisone; Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Dibucaine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Ethyl Chloride: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Hydrocortisone; Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Menthol; Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Pramoxine; Zinc Acetate: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Tretinoin; Benzoyl Peroxide: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.

Lidocaine, Tetracaine/Pliaglis Topical Cream: 7-7%
Synera Topical Film: 70-70mg

1 patch on the body at any given time; maximal application area of the cream should not exceed 62 inch2.

1 patch on the body at any given time; maximal application area of the cream should not exceed 62 inch2.

1 patch on the body at any given time; safety and efficacy of the cream have not been established.

3 years and older: 1 patch on the body at any given time; safety and efficacy of the cream have not been established.
Younger than 3 years: Safety and efficacy have not been established.

Mechanism of Action: Both lidocaine and tetracaine block the initiation and conduction of nerve impulses from sensory nerves by decreasing the permeability of the neuronal membrane to sodium ions. Sodium ion channel blockade reversibly stabilizes the membrane and inhibits depolarization, which results in the failure of a propagated action potential and subsequent conduction blockade. Due to interference with the transmission of impulses along sensory nerve fibers, lidocaine; tetracaine relieves pain. The blockade affects all nerve fibers in the following sequence: autonomic, sensory, and motor with effects diminishing in reverse order. Loss of nerve function clinically is as follows: pain, temperature, touch, proprioception, and skeletal muscle tone. Direct nerve membrane penetration is necessary for effective anesthesia, which is achieved by applying the anesthetic topically around the nerve trunks or ganglia supplying the area to be anesthetized.Systemic absorption of local anesthetics can produce effects on the central nervous and cardiovascular systems. Toxic blood concentrations depress cardiac conduction and excitability, which may lead to AV block, ventricular arrhythmia, and cardiac arrest. In addition, myocardial contractility is depressed and peripheral vasodilation occurs, leading to decreased cardiac output and arterial blood pressure. Local anesthetics can produce central nervous system stimulation, depression, or both following systemic absorption. Usually, CNS toxicity may be noted with a plasma lidocaine concentration of 5000 ng/ml, although toxicity may occur at concentrations around 1000 ng/ml. Central nervous system stimulation is usually manifested as restlessness, tremors, and shivering progressing to convulsions, depression, coma, and respiratory arrest. However, local anesthetics have a primary depressant effect on the medulla and higher centers. The depressed stage may occur without the prior excitatory stage.

Lidocaine; tetracaine is administered topically as a patch or cream. Lidocaine binds mainly to alpha-1-acid glycoprotein. After the recommended application of a Synera patch or of the cream (see Dosage and Administration), approximately 75% of lidocaine is bound to plasma proteins. At much higher plasma concentrations of 1—4 mg/ml of free base, the plasma protein binding of lidocaine is concentration dependent. Lidocaine crosses the placental and blood brain barriers, presumably by passive diffusion. Lidocaine is extensively metabolized by sequential N-deethylation in the liver into two active compounds, monoethylglycinexylidide and glycinexylidide, which possess 100% and 25% of the potency of lidocaine, respectively. The major metabolic pathway of lidocaine to monoethylglycinexylidide and glycinexylidide is primarily mediated by CYP1A2 with a minor role of CYP3A4. The half-life of lidocaine elimination from the plasma following intravenous administration is approximately 1.8 hours. Both lidocaine and its metabolites are renally excreted. It is not known if either lidocaine or tetracaine is metabolized in the skin. Tetracaine is hydrolyzed to para-aminobenzoic acid and diethylaminoethanol by plasma pseudocholinesterases. Tetracaine has the slowest rate of hydrolysis of the ester type local anesthetics and its metabolites are primarily renally excreted. The half-life for tetracaine has not been established due to rapid hydrolysis in the plasma.

Following application of a Synera patch to intact, adult skin for 30 minutes, the estimated absorbed dose of lidocaine was 1.7 mg and of tetracaine was 1.6 mg. The peak plasma concentration of lidocaine was 1.7 ng/ml and the tetracaine concentration was below the lower limit of quantification of 0.9 ng/ml. Application of a patch for up to 60 minutes did not significantly increase the plasma concentrations of either lidocaine or tetracaine. In contrast, lidocaine systemic exposure from the cream, as measured by Cmax and systemic exposure over 24 hours, was proportional to the application area and increased with application time up to 60 minutes. The amount of lidocaine and tetracaine systemically absorbed from the cream is directly related to both the duration of application and the surface area over which it is applied. Application of 21 grams of cream over 400 cm2 for 30 minutes results in a mean lidocaine Cmax of 49 ng/ml, obtained at a mean time of 4 hours after application. Application of 33 grams of cream to the same surface area for 60 minutes led to a mean Cmax of 96 ng/ml, which occurred at a mean time of 2.8 hours. Application of 59 g of over the same surface area for up to 120 minutes to adults produces peak plasma concentrations of lidocaine of 220 ng/ml. In each of these cases, tetracaine plasma concentrations were not measurable (< 0.9 ng/ml).
 
The anesthetic depth and duration achieved with a lidocaine; tetracaine patch was evaluated in a crossover study. As compared with a placebo patch, a lidocaine; tetracaine patch for 30 minutes led to a greater depth and duration of anesthesia. Anesthesia was determined by use of a scale (0 = no sensation, 1 = dull sensation, 2 = sharp, scratching sensation). The mean anesthetic depth was 6.8 mm as compared with 4.7 mm after placebo. Two patients had no pain after lidocaine; tetracaine at 10 mm of penetration, which was the study limit. Of the 12 patients, 10 had anesthesia with the lidocaine; tetracaine patch over the entire 2-hour post-application assessment period, and 11 of the patients had anesthesia at the 10, 20, 30, 40, and 50 minute assessments. In contrast, only 1 patient reported anesthesia with placebo, which occurred at the 10 minute assessment.
 
As determined by a pinprick test in 40 adults, the median duration of analgesia was 11 hours after 30 or 60 minutes of application of the cream. The mean time for return of sensation was similar between the 30- and 60-minute application periods. Diminished sensation at the end of the 13-hour study period was reported by 55% of patients.

There are no adequate data on the developmental risk associated with lidocaine; tetracaine use during human pregnancy. Drug-associated risks of major birth defects or miscarriage with parenteral lidocaine use during pregnancy were not observed from an epidemiologic study and case series. Systemic exposure to lidocaine; tetracaine is expected to be low compared to exposure following parenteral dosing, and the exposure is not expected to result in significant fetal exposure. In animal studies, lower fetal body weights were observed in the offspring of pregnant rats given a continuous subcutaneous infusion of lidocaine during organogenesis at doses approximately 1.3 times the maximum human recommended dose (MHRD) of 53 grams of lidocaine; tetracaine cream. Neonatal developmental delays were seen in offspring of pregnant rats who received lidocaine injection containing 1:100,000 epinephrine in the masseter jaw muscle or the gum of the lower jaw. No adverse embryofetal effects were seen following subcutaneous administration of tetracaine to pregnant rats and rabbits during organogenesis at 0.03 times the MHRD of lidocaine; tetracaine cream.

Lidocaine is excreted in breast milk with a milk:plasma ratio of 0.4 to 1.1 following parenteral administration. It is unknown whether tetracaine is excreted in breast milk. The low concentrations of lidocaine and tetracaine found in the plasma after topical administration are unlikely to cause adverse effects in the nursing infant. If used in the lactating mother, lidocaine; tetracaine should not be applied directly to the nipple and areola to avoid direct infant exposure. Consider the developmental and health benefits of breast-feeding along with the mother's clinical need for lidocaine; tetracaine and any potential adverse effects on the breast-fed infant from lidocaine; tetracaine or the underlying maternal condition.[31353] [52329]