Ontology highlight
ABSTRACT: Background
Levothyroxine (LT4) and rifampin (RIF) are sometimes used together; however, no clinical studies have assessed the effects of these drugs on thyroid function or the need to adjust LT4 dose.Methods
We retrospectively reviewed the records of 71 Korean patients who started RIF during LT4 treatment. Clinically relevant cases that required dose adjustment according to the American Thyroid Association (ATA)/American Association of Clinical Endocrinologists (AACE) guidelines were identified, and risk factors of increased LT4 dose were analyzed.Results
After administering RIF, median serum thyroid-stimulating hormone (TSH) level (2.58 mIU/L, interquartile range [IQR] 0.21-7.44) was significantly higher than that before RIF (0.25 mIU/L, IQR, 0.03-2.62; P < 0.001). An increased LT4 dose was required for 50% of patients in the TSH suppression group for thyroid cancer and 26% of patients in the replacement group for hypothyroidism. Risk factor analysis showed that remaining thyroid gland (odds ratio [OR] 9.207, P = 0.002), the time interval between starting RIF and TSH measurement (OR 1.043, P = 0.019), and baseline LT4 dose per kg body weight (OR 0.364, P = 0.011) were clinically relevant variables.Conclusions
In patients receiving LT4, serum thyroid function test should be performed after starting RIF treatment. For patients with no remnant thyroid gland and those receiving a lower LT4 dose, close observation is needed when starting RIF and TB medication.
SUBMITTER: Kim HI
PROVIDER: S-EPMC5231266 | biostudies-literature | 2017
REPOSITORIES: biostudies-literature
Kim Hye In HI Kim Tae Hyuk TH Kim Hosu H Kim Young Nam YN Jang Hye Won HW Chung Jae Hoon JH Moon Seong Mi SM Jhun Byung Woo BW Lee Hyun H Koh Won-Jung WJ Kim Sun Wook SW
PloS one 20170112 1
<h4>Background</h4>Levothyroxine (LT4) and rifampin (RIF) are sometimes used together; however, no clinical studies have assessed the effects of these drugs on thyroid function or the need to adjust LT4 dose.<h4>Methods</h4>We retrospectively reviewed the records of 71 Korean patients who started RIF during LT4 treatment. Clinically relevant cases that required dose adjustment according to the American Thyroid Association (ATA)/American Association of Clinical Endocrinologists (AACE) guidelines ...[more]