SYNERA - lidocaine and tetracaine patch
ZARS Pharma, Inc.
PATIENT PACKAGE INSERT
SYNERA� (lidocaine 70 mg and tetracaine 70 mg) topical patch
DESCRIPTION
Synera� consists of a thin, uniform layer of a local anesthetic formulation with an integrated, oxygen-activated heating component that is intended to enhance the delivery of the local anesthetic. The drug formulation is an emulsion in which the oil phase is a eutectic mixture of lidocaine 70 mg and tetracaine 70 mg. The eutectic mixture has a melting point below room temperature and therefore exists as a liquid oil rather than as crystals. The surface area of the entire Synera patch is approximately 50 cm2 , 10 cm2 of which is active.
Lidocaine is chemically designated as acetamide, 2-(diethylamino)-N-(2,6-dimethylphenyl), has an octanol:water partition ratio of 182 at pH 7.3
Tetracaine is chemically designated as 2-(dimethylamino)ethyl p-(butylamino)benzoate, has an octanol:water partition ratio of 5370 at pH 7.3.
Each Synera patch contains lidocaine 70 mg and tetracaine 70 mg in a eutectic mixture. The Synera formulation also contains the following inactive ingredients: polyvinyl alcohol, sorbitan monopalmitate, water, methylparaben and propylparaben.
The Synera heating component generates a mild warming that is intended to enhance the delivery of the local anesthetic. Synera begins to heat once the patch is removed from the pouch and is exposed to oxygen in the air. Although the patch may increase skin temperature by up to approximately 5�C, maximum skin temperature will not exceed 40�C. The heating component is composed of iron powder, activated carbon, sodium chloride, wood flour, water and filter paper.
CLINICAL PHARMACOLOGY
Mechanism of Action: Synera applied to intact skin provides local dermal analgesia by the release of lidocaine and tetracaine from the patch into the skin. Lidocaine is an amide-type local anesthetic agent and tetracaine is an ester-type local anesthetic agent. Both lidocaine and tetracaine block sodium ion channels required for the initiation and conduction of neuronal impulses, resulting in local anesthesia.
DOSAGE AND ADMINISTRATION
Synera should only be applied to intact skin.
Use immediately after opening the pouch.
For adults and children 3 years of age and older:
Venipuncture or Intravenous Cannulation: Prior to venipuncture or intravenous cannulation, apply Synera to intact skin for 20-30 minutes.
Superficial Dermatological Procedures: For superficial dermatological procedures such as superficial excision or shave biopsy, apply Synera to intact skin for 30 minutes prior to the procedure.
While efficacy has not been established for children less than 3 years of age, safe use of Synera in infants 4 to 6 months of age was documented in one study.
In general, simultaneous or sequential application of multiple Synera patches is not recommended. However, application of one additional patch at a new location to facilitate venous access is acceptable after a failed attempt.
If irritation or a burning sensation occurs during application, remove the patch.
When Synera is used concomitantly with other products containing local anesthetic agents, the amount absorbed from all formulations should be considered, as local anesthetics are thought to have at least additive toxicities.
