Flecainide Cimetidine

Drugs that may affect flecainide include amiodarone, cimetidine, cisapride, disopyramide, propranolol, ritonavir, urinary acidifiers/alkalinizers, and verapamil. Smoking may also have an effect. Drugs that may be affected by flecainide include cisapride, propranolol, and digoxin. 

Drugs that may affect amiodarone include hydantoins, cholestyramine, fluoroquinolones, rifamycins, ritonavir, and cimetidine. Drugs that may be affected by amiodarone include anticoagulants, beta-blockers, calcium channel blockers, cyclosporine, dextromethorphan, digoxin, disopyramide, fentanyl, flecainide, hydantoins, lidocaine, methotrexate, procainamide, quinidine, and theophylline. Drug/Lab test interactions Amiodarone alters the results of thyroid function tests, causing an increase in serum T4 and serum reverse T3 levels and a decline in... 

Drugs that may affect beta blockers include aluminum salts, barbiturates, calcium salts, cholestyramine, cimetidine, colestipol, diphenhydramine, hydroxychloroquine, NSAIDs, penicillins (ampicillin), rifampin, salicylates, SSRIs, sulfinpyrazole, calcium blockers, oral contraceptives, flecainide, haloperidol, hydralazine, loop diuretics,... 

In patients whose condition has been stabilized by flecainide, the addition of cimetidine may reduce the rate of flecainide s hepatic metabolism, increasing the potential for toxicity. Flecainide may increase digoxin concentrations on concurrent administration. 

Drug Interactions Other antihypertensive agents Carbamazepine (vasodilators, ACE inhibitors, Rifampin diuretics, and beta-blockers) Phenobarbital Digoxin Cyclosporine Disopyramide Theophylline Flecainide Inhalation anesthetics Quinidine Neuromuscular blocking agents Cimetidine Lithium ... 

FLECAINIDE H2 RECEPTOR BLOCKERS Cimetidine may t flecainide levels Cimetidine inhibits CYP2D6-mediated metabolism of flecainide. 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... 

Tjandra-Maga TB, van Hecken A, van Melle P, Verbesselt R, de Schepper PJ. Altered pharmacokinetics of oral flecainide by cimetidine. Br J Clin Pharmacol 1986 22(1) 108-10. 

CYP2C19 CYP2D6 diazepam, imipramine, 5-mephenytoin, omeprazol, proguanil, propranolol codeine, debrisoquine, dextromethorphan, flecainide, paroxetine, perphenazine, thioridazine carbamazepine, rifampicin cimetidine, felbamate fluoxetine, paroxetine, quinidine... 

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

After faking cimetidine 1 g daily for a week, the AUC of a single 200-mg dose of flecainide was increased by 28% in 8 healthy subjects. The fraction of flecainide excrefed unchanged in the urine was increased by 20%, but the total renal clearance was not altered. In another study in 11 patients, cimetidine 1 g daily for 5 days almost doubled the plasma levels of flecainide 200 mg daily measured 2 hours after the morning dose. ... 

Uncertain, but it is thought that the cimetidine reduces the hepatic metabolism of flecainide. ... 

An established but not extensively documented interaction. The clinical importance appears not to have been assessed, but be alert for the need to reduce the flecainide dosage if cimetidine is added. Caution is recommended in patients with impaired renal function, as the interaction is likely to be enhanced. ... 

Nitsch J, Kohler U, Ne3rses L, Ltiideritz B. Flecainid-Plasmakonzenliaicnen bei Hemmur des hepatischen Metabolismus durch Cimetidin. Klin Wo( iensdir (1987) 65 (Siq>pl IX), 250. 

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