Thyroid function following intravenous pyelography

Thyroid function was assessed by total serum thyroxine, free thyroxine index and serum triiodothyronine immediately prior to intravenous pyelography in 105 female outpatients. The thyroid function tests were repeated two months later. Although all three parameters showed a statistically significant mean rise, the changes were small and not clinically significant. Two patients from the study population with a past history of thyrotoxicosis had a transient elevation in serum triiodothyronine but neither patient developed clinical features of hyperthyroidism.