Short-term effect of acetylsalicylic acid analogue on pituitary-thyroid axis and plasma cortisol level in healthy human volunteers.

The effect of acetylsalicylic acid analogue (aloxiprinum; Superpyrin Spofa) administered perorally in a daily dose of 1 g per 10 kg body weight on serum levels of free thyroxine (FT4), total thyroxine (T4), triiodothyronine (T3), cortisol (F) and thyrotrophin (TSH) was studied in healthy human volunteers. In a first experiment the drug was administered for 3 days to 7 subjects, the total daily dose being divided into 4-5 aliquots, while the same total dose was administered within 4 h to another 8 subjects in a second experiment. In both experiments a highly significant increase of FT4 was found during the period of treatment, while the levels of other hormones i.e. (T3, T4, F and TSH) were decreased, in most cases significantly. After the withdrawal of the drug there was not only a return of all levels to the initial value, but in most cases an "overshoot" above this value was detected.