 Furthermore, alcohol enhances acetylation of procainamide to NAPA and alcohol consumption may reduce half-life.It also has been shown that coadministration of para-aminobenzoic acid decreases the biotransformation of procainamide to acecainide in a patient with rapid acetylation kinetics.Measuring the ratio of acecainide and procainamide concentrations together helps to achieve an optimum anti-arrhythmic effect and reduce the risk of toxicity.