Materials and Methods: In this qualitative study, we conducted in-depth semi-structured interviews with 12 MS patients, two parents, two spouses, one child, two experienced nurses in neurology wards, two neurologists, one physiotherapist, one pharmacy technician and MS medications supplier, and one director at MS Society. Data were collected from 2017 to 2020 and analyzed with a conventional content analysis approach.

Results: The analyses yielded four main themes and some related subcategories as the barriers to adherence to treatment regimens in MS patients: "discouraging treatment team" (similar symptoms and multiple differential misdiagnoses, delayed diagnosis and loss of treatment time, misinforming the patient, disparaging and mechanical view of the patient, damage to the trust-based relationship and developing defensive medicine, inappropriate interference of other medical team staff in doctors" job, lack of compassion and disregard for the patient"s educational and medical needs, lack of effort to gain patient trust, doubts about adherence to the treatment regimen, doctor-patient disagreement about the treatment); "disappointing family" (poor cooperation, negative behaviors, misconduct of the spouse"s family, fear and misconceptions); "ignorant society" (hasty judgments, weak culture, economic sanctions); and "personal problems" (devastating unemployment, debilitating economic poverty, disappointment in the future).

Conclusions: Adherence to treatment regimens in Iranian MS patients is associated with individual, family, and social factors and health care providers, such that they can discourage the patients from adhering to their treatment regimens. The focus of the treatment team staff on these factors can help promote adherence to the treatment regimen in MS patients and reduce the recurrence of the disease and readmissions to hospitals.