[Subcutaneous administration of levothyroxine in refractory hypothyroidism]

Hypothyroidism can usually be treated effectively with oral levothyroxine (LT-4) supplementation. However, hypothyroidism refractory to treatment with LT-4 is a common clinical condition. Causes include poor compliance, interactions with food or other medications, and gastrointestinal diseases, such as inflammatory bowel disease and short bowel syndromes. Increasing the oral dose of LT-4 is not always effective in these scenarios. Therefore, other routes of administration may be necessary. In this report, we evaluate alternative treatment modalities for refractory hypothyroidism and present two patients with intestinal malabsorption successfully treated by subcutaneous administration of LT-4.