Is TSH Schilddrüse useful for fatigue?

TSH (thyroid-stimulating hormone) is a key first-line marker for assessing thyroid function. Hypothyroidism can cause fatigue, so TSH testing is reasonable in unexplained fatigue. However, fatigue is multifactorial – iron deficiency, vitamin D deficiency, sleep disorders, and stress are also common causes. A single TSH value is insufficient; a full thyroid panel (fT3, fT4, antibodies) may be needed. Evidence for TSH in fatigue is clinically established (practice guideline), but not every fatigue case requires thyroid workup. Caveat: self-tests without physician interpretation can be misleading. Persistent fatigue warrants a comprehensive medical evaluation.