Hypothyroidism and High Plasma and Urine Iodine Levels Related to the Use of Gastrografin

We report the effect of Gastrografin on thyroid function in 7 neonates. Levels of free thyroxine and thyroid stimulating hormone, serum and urine iodine concentrations were determined before and after using gastrografin. Transient hypothyroidism was seen in 3 patients. No thyroid gland dysfunction was detected in the Neonatal Screening Program for congenital hypothyroidism before the administration of Gastrografin and thyroid antibodies were negative. Urine and serum iodine concentrations were elevated after Gastrografin administration. Normal thyroid hormone concentrations were observed in the other four infants. We suggest careful evaluation of thyroid function whenever Gastrografin is used.