ABSTRACT. Trehalose has several novel anti-inflammatory and cell-protective functions. We hypothesized that lyophilized aspirin/trehalose could decrease the severity of aspirin-induced gastropathy. Thirteen dogs were assigned into aspirin, lyophilized aspirin/trehalose, and control groups, and the gastric lesions were assessed on gastroscopy with the modified Lanza scale. Another 6 dogs were used to measure the plasma aspirin concentration by high-performance liquid chromatography after aspirin or lyophilized aspirin/trehalose administration. The results indicated that lyophilized aspirin/trehalose induced less gastric ulceration than aspirin despite maintaining therapeutic concentrations of plasma aspirin in both the groups. Lyophilized aspirin/trehalose might be a solution to decrease aspirin-induced gastropathy.