The study investigates the therapeutic potential of AphaMax®, a concentrated extract from the blue-green algae Aphanizomenon flos-aquae, in a rat model of colitis induced by 2,4-dinitrobenzenesulfonic acid (DNBS). The findings demonstrated that preventive oral administration of AphaMax® significantly reduced the severity of colitis, as evidenced by improvements in clinical signs, macroscopic and microscopic colon damage, and decreased levels of inflammatory markers such as myeloperoxidase activity, pro-inflammatory cytokines (IL-1β, IL-6), and oxidative stress indicators, suggesting its potential as a complementary therapy for inflammatory bowel disease.