Effect of paracetamol (acetaminophen) on gastric ionic fluxes and potential difference in man.

Paracetamol has replaced aspirin as the analgesic of choice in many situations. The major reason is the damaging effect of aspirin on gastric mucosa. Alterations in gastric ionic fluxes and potential difference provide measures of aspirin-induced structural damage. We studied the effect of large doses of paracetamol (acetaminophen 2-0 g) on gastric ionic fluxes in man. In addition, the effect of 2-0 g paracetamol on gastric potential difference was compared with that of 600 mg aspirin. In contrast with salicylates, paracetamol caused no significant alteration in movement of H+ and Na+ ions over control periods. Aspirin causes a significant fall in transmucosal potential difference (PD) across gastric mucosa of 15 mv, while paracetamol cuased no significant change. Paracetamol in a dose four times that recommended does not alter gastric ionic fluxes or potential difference. These studies support choice of paracetamol as analgesic over aspirin where damage to gastric mucosa may be critical.