falsely low TSH and biotin
Last edited 10/2023 and last reviewed 10/2023
TSH may be falsely low in patients who take supplemental biotin, as biotin can interfere with some immunoassay platforms (1)
- enquire about biotin use at the time of testing in patients with convincing signs or symptoms of hypothyroidism and a normal TSH, and ask patients to stop biotin supplements for several days before thyroid function testing
NICE note:
- ask adults, children and young people with suspected thyroid dysfunction about their biotin intake because a high consumption of biotin from dietary supplements may lead to falsely high or low test results.
Reference:
- Siskind SM et al. Investigating hypothyroidism.BMJ2021;373:n993http://dx.doi.org/10.1136/bmj.n993
- NICE (October 2023). Thyroid disease: assessment and management