Effects of pre- and postprandial aspirin on gastric bleeding based on clinical data and in vitro study

Aspirin is a common anti-inflammatory agent. Clinical pharmacists have found an inconsistency in the timing of taking the medicine mentioned in the instructions of different brands of aspirin (100mg). To compare the effects of pre- and postprandial aspirin on gastric bleeding and assess the potential risk factors of aspirin caused gastric bleeding.Data from 100 patients taking enteric-coated aspirin tablets in the Second Hospital of Dalian Medical University were retrospectively analyzed. They included demography, medical history, brand of aspirin, time of taking medicine (pre-prandial or postprandial), gastric bleeding situation.The dissolution rates of aspirin were conducted in different pH media (1.0-6.8) by invitro study. Clinical data showed that enteric-coated aspirin tablets had no significant changes in the incidence of gastric bleeding before or after meals (10%). The in Vitro dissolution text suggested that enteric-coated aspirin tablets had no obvious release at pH 1.0-5.0 for 2h; however, at pH>6.8, about 80% of the drug was released within 45min. The results suggest that patients with an upset stomach should be advised to take aspirin before meals to prevent aspirin release in advance.