IRCT20250502065563N1 IRCT 2025-08-03 Dezfoul University of Medical Sciences The effect of vitamin B1 on patients with hypothyroidism Investigating the effect of vitamin B1 on thyroid hormones and lipid profile of patients with hypothyroidism receiving levothyroxine 2025-06-22 anticipated 49 Complete https://irct.ir/trial/83549 interventional Randomization: N/A, Blinding: Not blinded, Placebo: Not used, Assignment: Single, Purpose: Treatment. N/A Hypothyroidism. In the present before-and-after semi-experimental study, 49 patients with hypothyroidism between the ages of 30 and 50 years with TSH levels greater than 10 µIU/mL and T4 less than 4 ng/dL and serum Anti-TPO levels greater than 200 U/mL will be enrolled in the study with a diagnosis of hypothyroidism. Patients will receive the usual treatment for hypothyroidism, namely levothyroxine, and in the intervention group, in addition to levothyroxine, they will receive 300 mg of vitamin B1 tablet daily in the morning on an empty stomach and half to 1 hour before taking levothyroxine. The duration of the treatment period is 2 months. After the end of 2 months of treatment, blood samples will be taken from the patients and the variables of TSH, T4, Anti-TPO, TG, TC, LDL-C, HDL-C, and VLDL in the patients' serum will be measured. On the other hand, the LDL-C/HDL-C ratio and the atherogenic index will be calculated based on the formula (TG/HDL-C) log.. No - There is not a plan to make this available Justification or reason for not sharing IPD is In accordance with the principles of publishing and writing articles for this category of studies, the results of this study can be published as an average in the resulting article and will not be published individually.