Causes of treatment failure in primary hypothyroidism

Primary hypothyroidism is one of the most common endocrine diseases. Levothyroxine is the treatment of choice due to its efficacy, good tolerance, simplicity of a dose titration, low cost and long elimination half-life. Replacement therapy for hypothyroidism is simple and convenient, but from 30 to 60% of patients are in a state of decompensation. Over- or underreplacement with L-T4 may lead to serious adverse events such as decreased performance and mood, deterioration of health and quality of life, developing of cardiovascular diseases, cardiac arrhythmias and bone fractures. The most common reasons for failure to compensate for the disease are improper administration of the drug (after eating, drinking coffee and milk immediately after levothyroxine), non-compliance with storage conditions (use after the expiration date, excessive heat), insufficient patient adherence to treatment (skipping the drug), the effect of other medicines drugs (calcium, iron preparations, proton pump inhibitors, etc.), diseases of the gastrointestinal tract (atrophic gastritis, celiac disease). Given many factors influencing the achievement and maintenance of compensation for hypothyroidism, it is necessary to determine and, if possible, eliminate the main factor leading to decompensation before the dose adjustment.