BackgroundGastrointestinal intolerance is common in rheumatoid arthritis (RA) patients using methotrexate and may lead to treatment discontinuation. AimTo study the prevalence of gastrointestinal symptoms in a sample of RA methotrexate users as well as its possible association with clinical and epidemiological variables. MethodsCross-sectional study of 192 patients with gastrointestinal symptoms using the MISS (methotrexate intolerance severity score). Clinical and epidemiological variables were collected through chart review and direct questioning. Patients’ adherence to methotrexate was evaluated through Moriski–Green–Levin questionnaire. ResultsThe prevalence of gastrointestinal complaints was high with 55.7% of the sample classified as intolerant. Nausea and pain after drug ingestion were the most common reported complaints. This intolerance was associated with afro-descendant background (p=0.02); presence of associated fibromyalgia (p=0.04), concomitant use of glucocorticoids (p=0.03) and Jak inhibitors (0.03). A tendency towards association with leflunomide use was observed (p=0.06). Logistic regression was used to test drug associations with methotrexate intolerance, and showed that glucocorticoid use was independently associated with methotrexate intolerance OR=1.85; 95% CI=1.01–3.44; p=0.04. Route of administration, presence of previous gastric complaints, age and methotrexate dose did not interfere with MISS. MISS results were associated with moderate adherence to the drug. ConclusionsThere is a high rate of methotrexate intolerance that is more common in afro-descendants, those with associated fibromyalgia, glucocorticoid and Jak inhibitors users.