Lidocaine/prilocaine

Another topical anesthetic, similar to benzocaine, is lidocaine, which is used to relieve the pain of shingles (herpes zoster) infections. Lidocaine is called an amide anesthetic, because it is not an ester (the alcohol is replaced by an amide, the nitrogen group). Amide anesthetics are metabolized by the liver, and are less prone to cause allergic reactions. If an anesthetic has the letter i in the prefix (lidocaine, prilocaine, bupivacaine), it is an amide anesthetic. 

Benzocaine, cetacaine, EMLA cream, lidocaine, prilocaine, and... 

Procaine Amethocaine Lidocaine Prilocaine Bupivicaine Ropivicaine Mepivicaine... 

Schmidt SH, Anniko M, Hellstrom S. 1990. Electrophysiological effects of the clinically used local anesthetics lidocaine, lidocaine-prilocaine and phenol on the rat s inner ear. Eur Arch Otorhinolaryngol 248 87-94. 

Dibucaine (Nupercainal) Lidocaine Prilocaine (EMLA, LMX) Lidocaine/Tetracaine Transdermal (Synera)... 

Percutaneous drug absorption can present special problems in newborns, especially in preterm infants. While the skin of a newborn term infant may have the same protective capacity as the skin of an adult, a preterm infant will not have this protective barrier until after 2 to 3 weeks of life. Excessive percutaneous absorption has caused significant toxicity to preterm babies. Absorption of hexachlorophene soap used to bathe newborns has resulted in brain damage and death. Aniline dyes on hospital linen have caused cyanosis secondary to methemoglobinemia, and EMLA (lidocaine/prilocaine) cream may cause methemoglobinemia when administered to infants less than 3 months of age. 

Clinical use Tetracaine is employed by ophthalmologists for surface anesthesia as a 0.5 % solution and by endoscopists for anesthesia of mucous membranes including airways as a 2.0 % solution. For topical anesthesia, a 4.0 % cream of tetracaine can also be used, which is, however, less effective than a lidocaine/prilocaine cream in preventing venipuncture-induced pain in children (van Kan et al., 1997). A combination of tetracaine with adrenaline and cocaine (TAC) is widely used for repair of... 

Bloch Y, Levkovitz Y, Atshuler A, et al. Use of topical application of lidocaine-prilocaine cream to reduce injection-site pain of depot antipsychotics. Psychiatr Serv. 2004 55 940-941. 

Topical benzocaine, butamben, tetracaine, lidocaine, prilocaine Increased risk of methemoglobinemia... 

Absorption from mucous membranes on topical application varies according to the compound. Those that are well absorbed are used as surface anaesthetics (cocaine, lidocaine, prilocaine). Absorption of topically applied local anaesthetic can be extremely rapid and give plasma concentrations comparable to those obtained by injection. This has led to deaths from overdosage, especially via the urethra. 

Taddio A, Ohlsson A, Einarson T, et al. A systemahc review of lidocaine-prilocaine cream for neonatal circumcision pain. N Engl J Med 1997 336 1197-1201. 

Engberg G, Danielson K, Henneberg S, Nilsson A. Plasma concentrations of prtiocaine and lidocaine and methaemoglobin formation in infants after epicutaneous application of a 5% lidocaine-prilocaine cream ( ra a). Acta AnaesthesiolScand(l9S7) 31, 624-8. 

Parenteral administration can be associated with pain at the injection site. The so-called injection fear may be diminished by applying topically anaesthetics prior to injection. Eutectic mixtures of local anaesthetics (e.g. lidocaine/ prilocaine cream or a tetracaine gel) have proven to be effective and well-tolerated in the relief of pain associated with intramuscular injections, venepuncture or intravenous injection in adults and children. 

One of the first uses of local anesthetics (LA) for anesthesia was in the late nineteenth century with William Halsted reporting a mandibular block and brachial plexus block using cocaine [37,38]. The chemical structure of local anesthetics in clinical use consists of an aromatic (lipophilic) benzene ring linked to an amino group (hydrophflic) via either an ester or an amide intermediate chain. The intermediate link classifies the local anesthetic as either an ester (procaine, chloroprocaine, tetracaine, and cocaine) or an amide (lidocaine, prilocaine, mepivacaine, bupi-vacaine, etidocaine, and ropivacaine). 

Generic Names topical lidocaine/prilocaine, topical lidocaine/tetracaine, tetracaine gel, 4% liposomal lidocaine, 1,1,1,3,3-pentafluoropro-pane and 1,1,1,2-tetrafluoroethane Trade/Proprietary Names EMLA (Eutectic Mixture of Local Anesthetics), Synera", Ametop Gel , LMX-4 , PainEase (vapocoolant spray)... 

Taddio A, Stevens B Craig K, Rastogi, P, Ben-David S, Shennan A, Mulligan P, Keren G. Efficacy and safety of lidocaine-prilocaine cream for pain during circumcision. N JMed 1997 336 1197-1201. 

Roldan-Marin R, de-la-Barreda Becerril F. Petechial and purpuric eruption induced by lidocaine/prilocaine cream a rare adverse effect. J Drugs Dermatol 2009 8(3) 287-8. 

A safe IV line is always necessary, and our preference goes to an antecubital catheter. The largest possible size is chosen. Placement of the catheter is ideally performed by a nurse in the outpatient suite after skin preparation with anesthetic cream (lidocaine-prilocaine, Emla ). This catheter makes it possible to use a power injector. Power injection provides an excellent examination quality, and continuous flow decreases the risk of extra vascular passage. The injection should be visually monitored and stopped in case of extra-vascular passage. In younger children, hand injection under visual control seems safer. 

Rubin MG 1995 The efficacy of a topical lidocaine/prilocaine anesthetic gel in 35% trichloroacetic acid peels. Dermatologic Surgery 21(3) 223-225... 

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