Thyroid Check (Schilddrüsen-Check)

A complete thyroid function panel measuring TSH, free T3, and free T4. While TSH alone is widely used as a screening marker, adding free T3 and free T4 reveals subclinical dysfunction and conversion issues that single-marker testing misses. Relevant for investigating fatigue, unexplained weight changes, hair thinning, or mood disturbances with a potential thyroid component.

Thyroid hormones regulate metabolic rate, energy production, and body temperature. TSH from the pituitary gland controls thyroid output, but testing TSH in isolation can miss clinically important patterns — particularly impaired conversion of the storage hormone T4 to the active hormone T3. This conversion failure may occur with selenium or iron deficiency, chronic stress, or certain medications, producing symptoms despite apparently normal TSH levels. This panel captures all three markers to provide a complete picture: TSH for pituitary-thyroid signalling, free T4 for the thyroid gland's primary output, and free T3 for the biologically active hormone that cells use directly. Discordance between these values often points to early autoimmune thyroid disease, conversion inefficiency, or medication interference that TSH-only screening would overlook. For the most consistent TSH readings, a morning blood draw before 10am is recommended, as TSH follows a circadian rhythm with peak values in the early morning hours. No fasting is specifically required for thyroid markers alone, though fasting may be advisable if combining this panel with glucose or lipid tests in the same draw.