Mexiletine Cimetidine

Drugs and chemicals are known to cause activated interaction. The depressant action of opioid drugs is enhanced by drugs acting on the central nervous system (CNS) such as alcohol, anesthetics, anxiolytics, hypnotics, tricyclic antidepressants, and antipsychotics. Concomitant administration of opioid analgesics and monoamine oxidase inhibitors (MAOIs) should be avoided, or extra care should be taken if such a therapy is inevitable. Fatal reactions are reported when treated along with selegiline. Interactions also are reported with cyclizine, cimetidine, mexiletine, cisapride, metoclopramide, or domperidone. 

Drugs that may affect mexiletine include aluminum-magnesium hydroxide, atropine, narcotics, cimetidine, fluvoxamine, hydantoins, metoclopramide, propafenone, rifampin, urinary acidifiers, and urinary alkalinizers. 

Drugs that may be affected by mexiletine include cimetidine, caffeine, and theophylline. 

Agents that may increase theophylline levels include allopurinol, beta blockers (nonselective), calcium channel blockers, cimetidine, oral contraceptives, corticosteroids, disulfiram, ephedrine, influenza virus vaccine, interferon, macrolides, mexiletine, quinolones, thiabendazole, thyroid hormones, carbamazepine, isoniazid, and loop diuretics. 

A2 Fluvoxamine Ciprofloxacin, mexiletine, propafenone, zileuton Acyclovir, cimetidine, famotidine, norfloxacin, verapamil... 

MEXILETINE H2 RECEPTOR BLOCKERS Cimetidine may t plasma concentrations of mexiletine Cimetidine inhibits CYP2D6-mediated metabolism of mexiletine. Ranitidine is a much weaker CYP2D6 inhibitor Monitor PR and BP at least weekly until stable. Warn patients to report symptoms of hypotension (lightheadedness, dizziness on standing, etc.). Consider alternative acid-suppression therapy... 

D6 Amiodarone, cimetidine, quinidine, SSRIs Antidepressants, flecainide, lidocaine, mexiletine, opioids... 

The pharmacokinetics of mexiletine were not altered by cimeti-dine or ranitidine. Cimetidine can reduce the gasitric adverse effects of mexiletine. 

Klein AL, Sami MH. Usefulness and safety of cimetidine in patients receiving mexiletine for ventricular arrh34hmia./imi7eartJ (1985) 109,1281-6. 

Klein A, Sami M, Selinger K. Mexiletine kinetics in healthy subjects taking cimetidine. Clin Pharmacol Ther (198 37,669-73. 

Brockmeyer NH, Breitha t H, Ferdinand W, von Hattit berg M, Ohnhaus EE. Kinetics of oral and intravenous mexiletine lack of effect of cimetidine and ranitidine. EurJ Clin Pharmacol 19 9)26,215-. ... 

In addition, the US manufacturer also recommends caution if tizanidine is given with other inhibitors of CYP1A2, of which they mention amio-darone, mexiletine, propafenone, cimetidine and ticlopidine. For a list of clinically important CYP1A2 inhibitors, see Table 1.2 , (p.4). 

Selertive serotonin reuptake inhibitors may decrease metabolism of alpha/beta blockers, benzodiazepines, carbamazepine, cimetidine, clozapine, fesoterodine, haloperidol, methadone, mexiletine, phenytoin, propafenone, respiradone, tamoxifen, galantamine, respiradone, thioridazine. 

Are there contraindications to concomitant drug use For instance, tizanidine is contraindicated in patients with concomitant use of CYP450 1A2 inhibitors such as fluvoxamine, amiodarone, mexiletine, propafenone, cimetidine, fluoroquinolones (ciprofloxacin, norfloxacin), rofecoxib, oral contraceptives, and ticlopidine [27]. 

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