We Have Some Trouble with Special Characters and Displaying Monographs. 22.09.2018 ATC Code: D04AB01 Classification

We have some trouble with special characters and displaying monographs. 22.09.2018

ATC code: D04AB01 Classification: PNP - Probably not porphyrinogenic Substance: Lidocaine Rationale for risk classification: Lidocaine is metabolized by CYP1A2, with only a minor contribution from CYP 3A4. Lidocaine is not listed as an inducer or as a mechanism-based inhibitor of CYP enzymes, nor is there any evidence of lidocaine capacity for Cyp-inhibition in clinical use. Lidocaine is reported as used uneventfully by 68 patients, and thus strong clinical evidence points to lidocaine as probably not porphyrinogenic. The systemic availability of lidocaine after restricted dermal use is usually low. Chemical description: Lidocaine hydrochloride is an amide derivative of diethyl amino acetic acid. Lidocaine has a lipophilic aromatic ring attached to a hydrophilic amino group by an amide linkage. Therapeutic characteristics: Lidocaine is a local anesthetic. In dermatological preparations lidocaine is used for the symptomatic relief of pain, itching or irritation of the skin or mucous membranes. It can be administered in topical formulations like ointment, gel or liniment for conditions like superficial skin wounds, insect bites, burns, herpes genitalis, and anal lesions or before various medical procedures. Extent of hepatic exposure: The plasma concentration of lidocaine is dependent on dose, administration method and vascularity of the site of administration. Whether the site of application has a traumatised or intact surface will also affect the absorption and systemic availability of the drug. Lidocaine is readily absorbed from mucous membranes and through damaged skin The hepatic exposure of lidocaine after restricted dermal use is probably not significant.. Systemic plasma concentrations after repeted anorectal administration of 5 % lidocaine ointment was found to be below uM (Zimmermann 2007).

Copyright 2007-2018 The Drug Database. All rights reserved.Page 1/4 Metabolism and pharmacokinetics: The primary metabolic pathway of lidocaine is CYP1A2 and, to a minor extent, CYP3A4 mediated N-deethylation to the active monoethylglycinexylidide (MEGX). MEGX is further de-ethylated to 2,6-xylidine and glycinexylidide. 2,6-xylidine is hydrolysed by CYP 2A6 to 4-hydroxy-xylidine, which is the major metabolite found in urine. In vitro studies suggest that CYP 3A4 may be an important contributor to the N-deethylation of lidocaine in high concentrations (above therapeutic concentrations) (Wang 2000). Found to be a week inhibitor of CYP 1A2 (Kobayashi 1998), and suggested as a competitive inhibitor of CYP1A2 by Wei (1999). In another study lidocaine was found to competitively inhibit N-monodesethylation of amioderone (with Ki = 120 Ã‚ÂµM) (Kobayashi 1998). Rendic (2002) reports that lidocaine is a substrate and an inhibitor of CYP1A2, a substrate for CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C18, CYP3A4 and an inhibitor and a substrate of CYP2D6. There is no evidence of lidocaine capacity for Cyp-inhibition in clinical use. Some studies have shown an accumulation of lidocaine or/and MEGX in continued administration of lidocaine (Miyabe 1999, Thomson 1987, Bauer 1982, Ngo 1997). One study report signs of CYP 3A4 TDI in rodent microsome experiments (Bensoussan 1994), but this has not been confirmed in human studies. Preclinical data on porphyrinogenicity: Lidocaine was found to increase the activity of delta-aminolaevulinic acid synthase in a rat liver model (Parikh, R.K. & Moore, M.R., 1978). Lidocaine was found to induce delta-aminolaevulinic acid synthase and to cause accumulation of porphyrins and cytochrom P450 in chick embryo livers in ovo (de Verneuil, H., Deybach, J.C. et al, 1982). Summary of other guidance on prescribing (porphyria drug lists): Porphyria South Africa: Use. Martindale: The Complete Drug Reference: Lidocaine is considered to be unsafe in patients with porphyria because it has been shown to be porphyrinogenic in animals. European Porphyria Initiative: Safe, intravenous doses should be avoided. Personal communications: Thunell, S., study to be published: Uneventfully used (mainly in dental procedures) by 45 patients. After the completion of the study, one instance of possible activation of the disorder following the use of lidocaine for dental surgery in a middle-aged male carrier of AIP was reported (other precipitating factors can not be excluded).

Copyright 2007-2018 The Drug Database. All rights reserved.Page 2/4 EPNET drug reports: Uneventful use reported in 3 patients with acute porphyria. Uneventful use is also reported after use of lidocaine under other ATC codes; N02BB02 used in 9 patients, N02BB52 used in 9 patients, C01BB01 used in 1 patient, and R02AD02 used in 1 patient. One report of an attack of acute porphyria following the use of lidocaine (N02BB02) in a male with active AIP, but the attack is poorly documented. References: Bargetzi MJ, Aoyama T et al. Lidocaine metabolism in human liver microsomes by cytochrome P450IIIA4. Clin Pharmacol Ther 1989; 46(5):521-7. Bensoussan M, delaforge M,et al. Particular ability of cytochromes P450 3A to form inhibitory P450-iron-metabolite complexes upon metabolic oxidation of aminodrugs. Biochem Pharmacol 1995; 49(5):591-502. de Verneuil,H., Deybach,J.C. et al. Study of anaesthetic agents for their ability to elicit porphyrin biosynthesis in chick embryo liver. Biochem Pharmacol 1982; 32: 1011-18. Kobayashi K, Nakajima M, et al. Inhibitory effects of antiarrhythmic drugs on phenacetin O-deethylation catalysed by human CYP1A2. Br J Clin Pharmacol. 1998 Apr;45(4):361-8. McEvoy GK, editor. Lidocaine Hydrochloride. The AHFS Drug Information 2008. Bethesda, MD: American Society of Health-System Pharmacists; 2009. Electronic version (February 2009). Miyabe M, Kakiuchi Y, et al, The plasma concentration of lidocaines principal metabolite increases during continuous epidural anesthesia in infants and children. Anesth Analg. 1998 Nov;87(5):1056-7. Ngo LY, Tam YK, et al Effects of intravenous infusion of lidocaine on its pharmacokinetics in conscious instrumented dogs. J Pharm Sci. 1997 Aug;86(8):944-52. Norwegian medicines agency. Summary of Product Characteristics (SPC). Xylocain. http://www.legemiddelverket.no/legemiddelsok (Last edition: 28.04.2006). Orlando R, Piccoli P et al. Cytochrome P450 1A2 is a major determinant of lidocaine metabolism in vivo: effects of liver function.Clin Pharmacol Ther 2004;75(1):80-8. Parikh, RK, Moore, MR. Effect of certain anaesthetic agents on the activity of rat hepatic delta-aminolaevulinate synthase. Br J Anaesth 1978; 50:1099-1103. Rendic, S. Summery of information on human CYP enzymes: human P450 metabolism. Drug metabolism

Copyright 2007-2018 The Drug Database. All rights reserved.Page 3/4 reviews 2002; 34(1&2), 83Ã¢â‚¬â€œ448. Sweetman SC, editor. Martindale: The complete drug reference. Lidocaine Hydrochloride. Pharmaceutical Press 2009. Swedish medicines agency. Summary of Product Characteristics (SPC) Xylocain 2 % gel. http://www.lakemedelsverket.se/Sok-efter-lakemedel-och-mediciner-i-Lakemedelsfakta. (Last updated: 18.09.2007). The electronic Medicines Compendium (emc). Summary of Product Characteristics (SPC). LMX4 Lidocaine. http://www.medicines.org.uk/EMC/. (Last edition: 15.03.2010). Thomson AH, Kelman AW, et al. Changes in lignocaine disposition during long-term infusion in patients with acute ventricular arrhythmias. Ther Drug Monit. 1987 Sep;9(3):283-91. Thunell, S. Evidence-based porphyrogenicity assessment of seven local anasthetics (2011, to be published). Wang B, Zhou SF.Synthetic and natural compounds that interact with human cytochrome P450 1A2 and implications in drug development. Curr Med Chem. 2009;16(31):4066-218. Wang JS, Backman JT, et al. Involvement of CYP1A2 and CYP3A4 in lidocaine N-deethylation and 3-hydroxylation in humans. Drug Metab Dispos. 2000 Aug;28(8):959-65. Wei X, Dai R, et al. Inhibition of human liver cytochrome P450 1A2 by the class IB antiarrhythmics mexiletine, lidocaine, and tocainide. J Pharmacol Exsperim Ther 1999 May;289(2):853-8 Zimmermann J, Schlegelmilch R, Proof of systemic safety of a lidocaine ointment in the treatment of patients with anorectal pain. Arzneimittelforschung. 2007;57(1):12-9.