ObjectiveInflammatory bowel diseases (IBD), such as Crohn’s disease (CD) and ulcerative colitis (UC), are chronic conditions primarily affecting the intestines. This study aims to identify the nature and frequency of oral symptoms and signs in patients with ulcerative colitis and to explore the connection between these complications and the activity of the disease.MethodsThis descriptive-analytical study involved ulcerative colitis patients who visited the gastroenterology clinic at Shahid Sayad Shirazi Hospital in Gorgan, along with an equal number of healthy companions as a control group in 2019. A gastroenterology internist assessed the disease severity through clinical examination and a simple clinical disease activity index for colitis patients. The collected data were then analyzed statistically using SPSS version 19.ResultsThe average age of patients in the case group was 41.84 ± 11.66 years, while in the control group it was 40.43 ± 12.67 years. There was a significant correlation between difficulty swallowing, burning sensation in the mouth, vomiting, acidic taste, the presence of oral ulcers, and a coated tongue with the severity of disease activity (p < 0.05). However, no significant relationship was found between other variables and the severity of disease activity (p > 0.05).ConclusionThe results of this study confirm that as the severity of ulcerative colitis increases, the occurrence of oral lesions also rises, particularly during severe disease activity. Among oral symptoms, dry mouth had the highest incidence, followed by bad breath and changes in taste. The most common oral lesions observed were a coated tongue, grooved tongue, and oral ulcers, respectively.