Interactions, drug procainamide

The many drug interactions described with cimetidine are largely attributable to inhibition of CYP isozymes or renal clearance of other drugs. Cimetidine also reduces hepatic blood flow and so can, for example, reduce the clearance of lidocaine. In the kidneys cimetidine interferes with the tubular excretion of procainamide and quinidine. Both effects are small, and the long list of drugs for which interference is demonstrable (Table 1) is out of all proportion to the number for which interference is of chnical significance. 

Bauer LA, Black D, Gensler A. Procainamide-cimetidine drug interaction in elderly male patients. J Am Geriatr Soc 1990 38(4) 467-9. 

Somogyi A, McLean A, Fleinzow B. Cimetidine-procainamide pharmacokinetic interaction in man evidence of competition for tubular secretion of basic drugs. Eur J Clin Pharmacol 1983 25 339-345. 

Cimetidine increases plasma concentrations of procainamide in humans. There are no reported drug interactions for procainamide in the horse (Muir Mcguirk 1987). 

A) A possible drug interaction with digoxin suggests that digoxin blood levels should be obtained before and after starting procainamide... 

Hughes B, Dyer JE, Schwartz AB. Increased procainamide plasma concentrations caused by quinidine a new drug interaction. Am Heart J (1987) 114, 908-9. 

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... 

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