Stork C M, Rees S, Howland M A, Kaplan L, Goldfrank L, Hoffman R S
New York City Poison Control Center, Bellevue Hospital Center New York, USA.
J Toxicol Clin Toxicol. 1996;34(2):157-62. doi: 10.3109/15563659609013764.
The purpose of this trial was to compare the pharmacokinetics of the two available acetaminophen dosage forms in simulated human overdose.
Ten healthy volunteers received acetaminophen, 75 mg/kg orally, either as the regular release or extended relief formulation in a random, crossover fashion. Blood samples were analyzed using a TDx assay and a best fit correlation of data points was determined by PCNONLIN.
The area under the curves for extended relief acetaminophen and regular release acetaminophen were 426 mg h/L and 432 mg h/L, respectively (p = 0.768). The mean half times for extended relief acetaminophen and regular release acetaminophen were 4.02 h and 2.56 h, respectively (p < 0.001). The mean maximum serum acetaminophen concentrations were 62.6 mg/L (414.4 mmol/L:) and 94.3 mg/L (624.3 mmol/L) for extended relief acetaminophen and regular release acetaminophen, respectively (p < 0.001) and the mean time to maximum serum acetaminophen concentrations were 0.87 h and 0.75 h for extended relief acetaminophen and regular release acetaminophen, respectively (p = 0.508).
Although the formulations appear to have equal bioavailability, their half-lives and peak concentrations were significantly different. Further study is required to determine whether these differences affect the assessment and management of poisoned patients.
