Abstract Background Mesalazine (5-ASA) is the standard first-line therapy for mild-to-moderate ulcerative colitis (UC). However, real-life adherence remains suboptimal and is influenced by multiple behavioral, cultural, therapeutic, and structural factors. Evidence from North African populations is scarce. This study aimed to identify major determinants of mesalazine non-adherence in a Moroccan UC cohort. Methods This retrospective descriptive study covered an 2 years period (September 2023–September 2025), during which all consecutive adult patients with mild-to-moderate UC receiving mesalazine were included. Data collected included dosing frequency, pill burden, cultural and behavioral perceptions, drug availability, formulation accessibility, financial limitations, and response to targeted education. Poor adherence was defined as taking 80% of prescribed doses. Frequencies and percentages were calculated. Results Thirty patients were enrolled, including 23 females and 7 males aged 23–57 years. Left-sided disease was most frequent (18 patients; 60%), followed by proctitis (8 patients; 26.7%) and pancolitis (4 patients; 13.3%). Good adherence was reported in 20/30 patients (66.7%), while 10/30 (33.3%) exhibited poor adherence. Among the poor adherence subgroup, stopping treatment when asymptomatic was the most frequent behavioral factor (6/10; 60%; 20% overall), followed by use of herbal alternatives (2/10; 20%; 6.7% overall), fear of medication (1/10; 10%; 3.3% overall), and forgetfulness (1/10; 10%; 3.3% overall). High pill burden (≥4 tablets/day) affected 16/30 patients (53.3%). Once daily mesalazine was used in 6/30 patients (20%), whereas 24/30 (80%) received multiple dose regimens. Drug unavailability affected 1/30 patients (3.3%), while financial constraints limiting regular drug purchase were reported by 8/30 (26.7%). Targeted counseling improved adherence in 7/10 poor adherence patients (70%). Conclusion Mesalazine non adherence among Moroccan UC patients is multifactorial, driven by behavioral habits, cultural beliefs, high pill burden, financial limitations, and structural barriers. Strategies to improve adherence should focus on simplifying dosing regimens, improving drug affordability and availability, and strengthening patient education programs. Conflict of interest: Mrs. Rizkou, Jihane: No conflict of interest Lairani, Fatima Ezzahra: No conflict of interest Nacir, Oussama: No conflict of interest Ait Errami, Adil: No conflict of interest Oubaha, Sofia: No conflict of interest Samlani, Zouhour: No conflict of interest Krati, Khadija: No conflict of interest
Rizkou et al. (2026) studied this question.