{"title":"Intramuscular and Subcutaneous Levothyroxine: Success in Treating Refractory Hypothyroidism.","authors":"Nadia Chaudhury, Winston Crasto, Ponnusamy Saravanan, Vinod Patel","doi":"10.1530/ETJ-25-0012","DOIUrl":null,"url":null,"abstract":"<p><strong>Introduction: </strong>Refractory hypothyroidism often poses a clinical problem as treatment regimens are difficult to individualise to the patient and feasibility of its delivery is difficult to organise within a health care system. We present a patient who became intolerant of intramuscular (IM) levothyroxine (LT4) after 18 years of treatment, thus subcutaneous (SC) LT4 was initiated.</p><p><strong>Case presentation: </strong>13-year-old female with newly-diagnosed hypothyroidism, remained hypothyroid despite escalating doses of oral LT4 and LT3. Thyroxine malabsorption was further suggested by nasogastric administration of LT4, whereby high dose thyroxine administration resulted in only 2.8 pmol/L increase in free T4 level (normal >5.14pmol/L). She eventually achieved long-term euthyroid status at age of 18 with fortnightly IM LT4, alongside oral LT4 and LT3. This was maintained for 18 years. Unfortunately, scar tissue developed around injection sites, resulting in increased pain and difficulty of administration. SC LT4 was trialled with success, and she has remained euthyroid for the last six years with self-administration and minimal side effects.</p><p><strong>Conclusion: </strong>Refractory hypothyroidism often presents a challenge for clinicians, both for diagnosis and management. We discuss a patient with longest follow-up to-date within the published literature for both IM and SC LT4 for patient-administered treatment of refractory hypothyroidism and review the literature on alternative formulations available.</p>","PeriodicalId":12159,"journal":{"name":"European Thyroid Journal","volume":" ","pages":""},"PeriodicalIF":3.5000,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"European Thyroid Journal","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1530/ETJ-25-0012","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENDOCRINOLOGY & METABOLISM","Score":null,"Total":0}
引用次数: 0
Abstract
Introduction: Refractory hypothyroidism often poses a clinical problem as treatment regimens are difficult to individualise to the patient and feasibility of its delivery is difficult to organise within a health care system. We present a patient who became intolerant of intramuscular (IM) levothyroxine (LT4) after 18 years of treatment, thus subcutaneous (SC) LT4 was initiated.
Case presentation: 13-year-old female with newly-diagnosed hypothyroidism, remained hypothyroid despite escalating doses of oral LT4 and LT3. Thyroxine malabsorption was further suggested by nasogastric administration of LT4, whereby high dose thyroxine administration resulted in only 2.8 pmol/L increase in free T4 level (normal >5.14pmol/L). She eventually achieved long-term euthyroid status at age of 18 with fortnightly IM LT4, alongside oral LT4 and LT3. This was maintained for 18 years. Unfortunately, scar tissue developed around injection sites, resulting in increased pain and difficulty of administration. SC LT4 was trialled with success, and she has remained euthyroid for the last six years with self-administration and minimal side effects.
Conclusion: Refractory hypothyroidism often presents a challenge for clinicians, both for diagnosis and management. We discuss a patient with longest follow-up to-date within the published literature for both IM and SC LT4 for patient-administered treatment of refractory hypothyroidism and review the literature on alternative formulations available.
期刊介绍:
The ''European Thyroid Journal'' publishes papers reporting original research in basic, translational and clinical thyroidology. Original contributions cover all aspects of the field, from molecular and cellular biology to immunology and biochemistry, from physiology to pathology, and from pediatric to adult thyroid diseases with a special focus on thyroid cancer. Readers also benefit from reviews by noted experts, which highlight especially active areas of current research. The journal will further publish formal guidelines in the field, produced and endorsed by the European Thyroid Association.