N-acetyl procainamide

The N-acetyl procainamide (NAPA) metabolite blocks rapid potassium channels. cHas p-blocking properties. 

The simultaneous administration technique was used to study a 64-year-old man with a creatinine clearance of 79 mL/ min who was started on N-acetyl-procainamide (NAPA) therapy for ventricular arrhythmias (see Figure 4.4). The oral NAPA dose was 66% absorbed in this patient, compared to 91.6 9.2% when this method was used to assess NAPA absorption in normal subjects. Although this approach is ideally suited for studies of drug absorption in various patient populations, the required additional chemical synthesis of stable isotope-labeled drug and mass spec-trometric analysis of patient samples have precluded its widespread adoption. 

Procainamide NAPA (n-acetyl procainamide) a procainamide metabolite 4-10 mcg/mL Trough 4 mcg/mL Peak 8 mcg/mL 10-30 mcg/mL Trough Immediately prior to next dose or 12-18 h after starting or changing an infusion Draw with procainamide sample ... 

Procainamide N-acetyl procainamide Distinct antiarrhythmic activity, the mechanism of which is different from that of the parent compound... 

ISOM inner stripe outer medulla NAPA N-acetyl procainamide... 

Orally effective, often substituting for quinidine. Metabolized via N-acetyltrans-ferase (genotypic variation) to N-acetyl procainamide (NAPA), an active metabolite, which prolongs APD. With IV use, this is less likely to occur. 

Metabolized via M-acetyltransferase (genotypic variation) to N-acetyl procainamide (NAPA), an active metabolite... 

It is also reported that 65% of the administered dose (750 mg) is excreted in the urine as procainamide and the remaining 35% of the dose appears in the urine as a metabolite (N-acetyl-procainamide). Determine the amount of procainamide (i.e. amount excreted) in urine at 4h, the amount of N-acetylprocainamide (i.e. amount of metabolite) in urine at 4h and the total amount of dmg eliminated at 4 h, following the administration of a 450 mg dose. 

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