Subjective gastrointestinal tolerability of acetylsalicylic acid and paracetamol after single dose treatment.

A prospective, randomised, double-blind, parallel group, two center, single-dose study was conducted to evaluate and compare the incidence of upper gastrointestinal complaints of acetylsalicylic acid and paracetamol. 600 healthy volunteers received acetylsalicylic acid (2 effervescent tablets of 400 mg), paracetamol (2 effervescent tablets of 500 mg) or placebo (2 effervescent tablets) in three treatment groups. Subjects filled in a questionnaire at 0.5, 1, 2, 3 and 4 h after dosing to evaluate eight upper gastrointestinal symptoms, which were stomach pain, burning sensation, nausea, heartburn, gas, burping, indigestion and upset stomach. The primary study objective was to show equivalence between acetylsalicylic acid and paracetamol.

RESULTS

The absolute number of subjects reporting gastrointestinal intolerance were 50 of 200 in the placebo group, 46 of 200 in the paracetamol group and 56 of 201 in the acetylsalicylic acid group. The statistical test showed equivalence between both active substances.

CONCLUSIONS

The rate of gastrointestinal intolerance following a single dose of two effervescent tablets of acetylsalicylic acid is equivalent to that of paracetamol and not different from gastrointestinal intolerance of placebo.