The treatment spectrum for ulcerative colitis has greatly increased in recent years. Mesalazine is still the standard drug treatment for uncomplicated ulcerative colitis in various forms of administration. Glucocorticoids are highly effective in the acute treatment of ulcerative colitis but should only be used on a short-term basis due to the pronounced side effects. For forms with a complicated course of ulcerative colitis, immunosuppressive and immunomodulating substances, such as azothioprine as well as various biologicals, Janus kinase inhibitors (JAKi), sphingosine-1-phosphate receptor agonists (S1PR agonists) and calcineurin inhibitors are available after failure of conventional treatment. A proctocolectomy should be considered in cases of a treatment-refractive course or with detection of carcinomas and high-grade epithelial dysplasia.