Conclusions
Several classes of medications can cause abnormal TFT results, in
euthyroid subjects, without any clinically apparent effect on thyroid
hormone secretion. The possible mechanisms are through assay
interference or changes in TBP levels or alterations in their affinity
for thyroid hormones. Awareness of these drug-related effects, is of
paramount importance as many of these changes, while not warranting any
medical intervention, can misguide the clinician in diagnostic and
therapeutic decision making.