SMS 201-995 and thyroid function in acromegaly: acute, intermediate and long-term effects.
The acute (TRH-stimulation test), intermediate (0-6 days administration), and long-term (0-30 months administration) effects of SMS 201-995 (octreotide) treatment on thyroid function were studied. Subcutaneous injection of 100 micrograms SMS 201-995 one hour before 200 micrograms TRH intravenously reduced serum TSH response area by more than 50% in 8 healthy volunteers. After 3 days of continuous subcutaneous infusion (CSI) of SMS 201-995 in 9 acromegalic patients (100 micrograms/24 h) a slight but significant decrease in serum total triiodothyronine (TT3) and a concomitant increase in serum TSH were demonstrated, indicating an initial inhibitory effect on peripheral deiodination of thyroxine. After a further 3 days treatment serum T3 and TSH had returned to prevalues. Six of the nine acromegalics were treated with SMS 201-995 (100-1500 micrograms/24 h) and admitted for diurnal hormone profiles on 13 occasions over 30 months. Apart from a barely significant increase in serum TSH, no changes in thyroid function were noted. The study was especially designed to detect minute changes over time in thyroid hormones. The only long-term effect of SMS 201-995 was the barely significant clinically irrelevant increase in serum TSH, possibly caused by a slight inhibition of peripheral deiodination of thyroxine.
Christensen
S E
SE
Medical Department M (Endocrinology and Diabetes), Aarhus Kommunehospital, Denmark.
Weeke
J
J
Kaal
A
A
Harris
A G
AG
Orskov
H
H
D000172:Acromegaly / Q000150:complications* / Q000188:drug therapy; D000328:Adult; D006801:Humans; D008297:Male; D008875:Middle Aged; D015282:Octreotide / Q000009:adverse effects* / Q000627:therapeutic use; D011863:Radioimmunoassay; D013960:Thyroid Function Tests; D013972:Thyrotropin / Q000097:blood; D013973:Thyrotropin-Releasing Hormone; D014284:Triiodothyronine / Q000097:blood
D014284:Triiodothyronine; D013973:Thyrotropin-Releasing Hormone; D013972:Thyrotropin; D015282:Octreotide