BACKGROUNDWhether combination therapy has higher hemostatic efficacy than epinephrine injection monotherapy in different Forrest classifications is not clear. This study aimed to compare hemostatic efficacy between epinephrine injection monotherapy (MT) and combination therapy (CT) based on different Forrest classifications.METHODSWe retrospectively analyzed peptic ulcer bleeding (PUB) patients who underwent endoscopic epinephrine injections or epinephrine injections combined with a second therapy between March 2014 and June 2022 in our center, and the patients were divided into MT group or CT group. Subsequently, a propensity score matching analysis (PSM) was performed and rebleeding rates were calculated according to Forrest classifications via a stratified analysis.RESULTSOverall, 605 patients who met the inclusion criteria were included, and after PSM, 173 patients in each of the CT and MT groups were included. For PUB patients with nonbleeding visible vessels (FIIa), the rebleeding rates by Days 3, 7, 14, and 30 after PSM were 8.8%, 17.5%, 19.3%, and 19.3% in the MT group, respectively, and rates were 0%, 4.1%, 5.5%, and 5.5% in the CT group, respectively, with significant differences observed between the two groups by Days 3, 7, 14, and 30 (P = 0.015, P = 0.011, P = 0.014, and P = 0.014, respectively). However, for PUB patients with oozing bleeding (FIb), the rebleeding rates by Days 3, 7, 14, and 30 after PSM were 14.9%, 16.2%, 17.6%, and 17.6% in the MT group, respectively, and rates were 13.2%, 14.7%, 14.7%, and 16.2% in the CT group, respectively, with no significant differences observed between the two groups by Days 3, 7, 14, and 30 (P = 0.78, P = 0.804, P = 0.644 and P = 0.825).CONCLUSIONCombined therapy has higher hemostatic efficacy than epinephrine injection monotherapy for PUB patients with visible blood vessel (FIIa) ulcers. However, epinephrine injection monotherapy is equally as effective as combined therapy for PUB patients with oozing blood (FIb) ulcers.