Thyroxine Replacement Therapy during Ramadan Fasting: Physicians' and Patients' Perceptions and Practices

Abstract Objective Thyroxine (T4) therapy is taken on an empty stomach and no food is taken for a short period. During Ramadan fasting (RF), Muslim patients may face difficulties taking levothyroxine as recommended. Materials and Methods We performed a mixed methods study of an online survey of 218 physicians to explore their perceptions and practices. Also, we interviewed a sample of 172 hypothyroid patients to establish their practices and source of information. Their median age was 46 (17–90) years; they had hypothyroidism for a median of 5 years and took a median thyroxine dose of 100 µg daily. Furthermore, we attempted to explore the effects of RF on available thyroid function tests. Results Consultants were 58.4%, and the most represented specialty was endocrinology, 46.1%. Regarding the impact of RF on T4 therapy, 52.3% thought the RF was not clinically relevant in most patients on T4 replacement. However, 27.5% thought RF affects T4 replacement therapy in a clinically relevant manner. About 77.1% of respondents reported giving advice routinely to all patients on T4 replacement during RF. One hundred sixty-four respondents were split between recommending taking the medications with Iftar, Suhour, or other times. Most respondents (73.9%) do not repeat measurements of thyroid hormone levels after Ramadan unless needed during their scheduled clinic visit. On the other hand, 50.3% of the patients confirmed that their physician advised them to take their thyroxine during Ramadan, whereas 40.4% could not recall receiving any advice. About 59.9% of the patients took thyroxine with Iftar, 23.8% with Suhour, and 16.3% at different times. In those patients where thyroid function tests were available before and after RF, serum thyroid-stimulating hormone and serum-free T4 did not show a specific pattern in the group as a whole and with subgroups. Conclusion There is variation in the advice that hypothyroid patients receive on taking thyroxine during Ramadan and in their practices. Further studies are needed to determine the best timing for thyroxine replacement.