Improving Levothyroxine Adherence and Thyroid- Stimulating Hormone Control via Structured Clinical Pharmacist-Led Education in Patients with Hypothyroidism

Objective: Hypothyroidism requires lifelong levothyroxine (LT4) therapy, yet achieving target thyroid-stimulating hormone (TSH) levels is often hindered by complex drug–food interactions and poor adherence. This study evaluated the impact of clinical pharmacist-led education on LT4 adherence and treatment effectiveness. 

Methods: This uncontrolled pre–post interventional study was conducted between November 2024 and April 2025 in an endocrinology outpatient clinic. Patients diagnosed with hypothyroidism initiating LT4 therapy were included. Baseline sociodemographic data and medication habits were recorded, and adherence was assessed using the Turkish-validated Medication Adherence Report Scale-5 (MARS-5). Participants received a 10-min structured verbal education session and an informative brochure. After 3 months, a follow-up was conducted via telephone to re-administer MARS-5 and retrieve serum TSH and free thyroxine (fT4) values from hospital records. 

Results: Among 152 participants (median age 51; 86.2% female), the median MARS-5 score significantly increased from 24.0 (interquartile range (IQR) 22.0-25.0) to 25.0 (IQR 24.0-25.0; P < .001). Median TSH levels significantly decreased from 2.04 (0.80-3.95) to 1.17 (0.39-3.16) mIU/L (P =.002), while fT4 levels remained stable. Notably, the proportion of patients taking LT4 at least 30 min before breakfast improved from 45.7% to 96.7% (P < .001). 

Conclusion: A brief, structured clinical pharmacist-led intervention significantly improved LT4 adherence and biochemical treatment outcomes. These findings underscore the clinical value of integrating pharmacist-led education and follow-up services into routine outpatient care to optimize long-term management of hypothyroidism. 

Cite this article as: Ustaömer S, Durmuş M, Üçüncü Ö, Koçak M. Improving levothyroxine adherence and thyroid-stimulating hormone control via structured clinical pharmacist-led education in patients with hypothyroidism. Endocrinol Res Pract. Published online September 1, 2026. doi: 10.5152/erp.2026.26986.