If a patient's thyroid hormone (T4) level increases significantly, which consequence follows due to feedback regulation?

💡 Explanation

High T4 levels trigger negative feedback, inhibiting the hypothalamus and pituitary from releasing TRH and TSH, because this reduces further T4 production via the hypothalamic-pituitary-thyroid axis. Therefore, TRH and TSH secretion decreases, rather than increasing hormone production further.

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