Mexiletine hydrochloride

Class I, Type IB Antiarrhythmics lidocaine hydrochloride mexiletine hydrochloride... 

Infra-red Spectrum. Principal peaks at wavenumbers 1200,1040, 770, 760,1595,1090 (mexiletine hydrochloride, KBr disk). 

Yamazaki S, Katayama I, Kurumaji Y, Yokozeki H, Nishioka K. Contact urticaria induced by mexiletine hydrochloride in a patient receiving iontophoresis. Br J Dermatol 1994 130(4) 538 0. 

Kayaba M, Tanaka T, Misago N, Narisawa Y. Three cases of hypersensitivity syndrome due to mexiletine hydrochloride. Nishinihon J Dermatol 2000 62 338 2. 

Kudo M, Ohke H, Kawai T, Kato M, Kokubu M, Shinya N. Geriatric patient who suffered transitory cardiovascular collapse under sevoflurane anesthesia due to continuous medication with mexiletine hydrochloride. J Jpn Dent Soc Anesthesiol 1999 27 614-18. 

Mexiletine Hydrochloride. Mcxiletinc hydrochloride. l-methyl-2-(2.6-xylyloxy)cthylamine hydrochloride (Mexi-til) (pK.., 8.4), is a class IB ontiarrhythniic agent that is cffec-tive when given either intravenously or orally. It re.sembles lidocaine in po.ssessing a xylyl moiety but otherwise is diTfer-ent chemically. Mexiletine hydrochloride is an ether and is not subject to the hydrolysis common to the amides lidocaine and tocainide. Its mean half-life on oral administration is approximately 10 hours. 

Although not subject to hydrolysis, mexiletine hydrochloride is metabolized by oxidative and reductive processes in the liver. Its mctabolitc.s,p-hydroxymexiletineand hydroxy-methylmcxiletine. arc nut pharmacologically active as anti-arrhythmic agents. ... 

Mexiletine hydrochloride, like cla.ss I antiarrhythmic agents, blocks the fast Na channel in cardiac cells. It is especially effective on the Purkinje fibers in the heart. The drug increases the threshold of excitability of myocardial cells by reducing the rale of rise and amplitude of the action potential and decreases aulomaliciiy. 

Mexiletine hydrochloride is u.sed fur long-term oral prophylaxis of ventricular tachycardia. The drug is given in 200-tu 400-mg doses every 8 hours. 

Mexiletine hydrochloride Pharmaceutical preparations Fluorimetry 2 to 30 10-300 mg L-1 Sequential injection chromatography with monolithic column/zone splitting [127]... 

P.D. Tzanavaras, C.K. Zacharis, P. Rigas, Novel automated assay for the quality control of mexiletine hydrochloride formulations using sequential injection and online dilution, J. Pharm. Biomed. Anal. 48 (2008) 1254. 

Lignocaine has already been diseussed under local anaesthetics and it is also found to possess anti-arrhythmic actions. There are a few other synthetic compormds which exhibit lignocaine-like properties, e.g., mexiletine hydrochloride tocainide which shall be discussed as rmder ... 

Class I anti-arrhythmic drugs normally prolong the refraetory period of cardiac muscle, re-duee its exeitability, and above all minimise the eonduetion veloeity for example, quinidine sulphate, disopyramide phosphate, toeainide hydrochloride, proeainamide hydroehloride, mexiletine hydrochloride, aprindine, ete. 

Mexiletine hydrochloride has been found to crystallize in six polymorphic forms, each of which yields a characteristic IR spectrum [118], As shown in the data collected in Table 4, the very intense bands due to the C-N(H) stretching mode (1020-1060 cm ) and the aromatic C-H out-of-plane deformation mode (760-780 cm ) were found to be particularly sensitive to the structural differences. In fact, the splitting of the latter mode observed in four of the six polymorphs suggests the existence of different types of molecules within the unit cell. The data in Table 4 also illustrate the typical magnitudes in band energy differences encountered within the vibrational spectra of polymorphic systems. 

Table 4 Effect of Crystal Polymorphism on Selected Infrared Bands of Mexiletine Hydrochloride...

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