Which pattern indicates hyperthyroidism?

Prepare for the Lab Values for Nurses Test. Utilize flashcards and multiple choice questions; each question offers hints and explanations. Enhance your readiness for the exam!

Multiple Choice

Which pattern indicates hyperthyroidism?

Explanation:
Hyperthyroidism raises the amount of thyroid hormone in the blood, and the pituitary responds by dialing TSH down. So the classic lab pattern is a low TSH with an elevated Free T4 (and often Free T3). Seeing a high TSH with a low Free T4 points to primary hypothyroidism, where the thyroid isn’t making enough hormone and the pituitary tries to compensate by producing more TSH. In hyperthyroidism, the high thyroid hormone would suppress TSH rather than raise it.

Hyperthyroidism raises the amount of thyroid hormone in the blood, and the pituitary responds by dialing TSH down. So the classic lab pattern is a low TSH with an elevated Free T4 (and often Free T3). Seeing a high TSH with a low Free T4 points to primary hypothyroidism, where the thyroid isn’t making enough hormone and the pituitary tries to compensate by producing more TSH. In hyperthyroidism, the high thyroid hormone would suppress TSH rather than raise it.

More practice questions