Bioequivalence study of two oral formulations of paracetamol

The pharmaceutical preparations of paracetamol Duorol and Termalgin, both containing 500 mg of active compound, were studied to test their bioequivalence. The results obtained showed that absorption of the drug follows two sequential kinetic processes by their corresponding first order rate constants (K1 and K2) with values of 0.31, 5.69 and 0.30, 5.71 h-1 for Duorol and Termalgin, respectively. Analysis of variance showed that there were no statistically significant differences (p greater than 0.5) in the absorption, biotransformation and excretion processes between the two preparations assayed. Finally, the use of symmetric confidence intervals by the Westlake test, showed that both preparations are bioequivalent.