5052 Hypothyroidism Management with Roux en Y Gastric Bypass

Abstract Disclosure: S.N. Vallabh: None. J. Swavely: None. A. Kattamanchi: None. Background: Roux en Y Gastric Bypass surgery has been shown to cause effective weight loss in individuals who qualify for the procedure. However, drug absorption is reduced in certain medications post-bariatric surgery. There is consistent evidence for diminished absorption in cyclosporine, thyroxine, phenytoin, and rifampin. No current literature found an association between levothyroxine liquid form and increased absorption status-post bariatric surgery. However, there are studies showing increased liquid absorption of levothyroxine in patients with suboptimal thyroid-stimulating hormone. Case presentation: The patient is a 60-year-old female with a past medical history significant for hypothyroidism and gastric bypass at the age of 21 years old who came in with the chief complaints of cold intolerance, fatigue, and hair loss. She was taking max dose of levothyroxine 300 mcg five days a week and 450 mcg two days out of the week and had an abnormal thyroid-stimulating hormone level of 340.47 the normal range is (0.45-5.33). The free thyroxine level was 0.44 the normal range is (0.61-1.24). The patient had been on oral Levothyroxine for decades, remaining symptomatic with elevated thyroid-stimulating hormone. The patient was trialed on liquid levothyroxine same dose. After the patient started a liquid regimen of her levothyroxine, her fatigue diminished, her cold intolerance lessened, her hair loss decreased, her thyroid stimulating hormone normalized to 0.91 the normal range is ( 0.4-4.50), and the free thyroxine increased to 2.1 the normal range is ( 0.8-1.8). Her levothyroxine dose was reduced to 300 mcg six days a week and 450 mcg 1 day a week. Conclusion: In conclusion, levothyroxine liquid form has been able to help normalize thyroid function in a patient with a remote history of bariatric surgery with severely uncontrolled hypothyroidism in spite of very high doses of levothyroxine. Bariatric surgery has been associated with weight loss and more stable thyroid levels. However, it also can lead to decreased absorption of oral levothyroxine. There are limited studies showing increased liquid absorption of levothyroxine in patients with bariatric surgery compared to oral form. More research needs to be conducted to see if liquid thyroxine leads to symptom abatement and its role in gastric bypass surgery for patients with hypothyroidism. Reference:•Virili, Camilla, et al. “Levothyroxine therapy: Changes of TSH levels by switching patients from tablet to liquid formulation. A systematic review and meta-analysis.” Frontiers in Endocrinology, vol. 9, 2018, https://doi.org/10.3389/fendo.2018.00010. •Zendel, Alex, et al. “The impact of bariatric surgery on thyroid function and medication use in patients with hypothyroidism.” Obesity Surgery, vol. 27, no. 8, 2017, pp. 2000–2004, https://doi.org/10.1007/s11695-017-2616-7. Presentation: 6/3/2024