[Individually dosed levothyroxine with 150 micrograms iodide versus 100 micrograms levothyroxine combined with 100 micrograms iodide. A randomized double-blind trial].
OBJECTIVE
Intrathyroid deficiency and the influence of thyroid stimulating hormone (TSH) are the main pathogenetic factors in the development of endemic euthyroid goitre. Goitre reduction is achieved with either administration of levothyroxine, which diminishes hypophyseal TSG production, or of iodide. Aim of this study was to compare the efficacy of treatment with a dose-fixed combination of levothyroxine plus iodide with that of an individualized dosage of levothyroxine plus iodide.


METHODS
After randomization 49 patients with euthyroid goitre (24 women, 25 men, aged 20-43 years) were treated for 12 weeks in a double-blind trial. Patients in group A received levothyroxine in a weight-adapted dosage (75,100 or 150 micrograms) plus 150 micrograms iodide, while those in group B were given a fixed dosage of 100 micrograms levothyroxine plus 100 micrograms iodide. Basal TSH, thyroid hormones, iodide excretion, hyperthyroid score and sonographic volume of the thyroid were determined before treatment and after 12 weeks.


RESULTS
Basal TSH levels were reduced in both groups (P < 0.0001), without significant difference between the two groups (median relative change: group A 78.1%, group B 52.8%). Thyroid volume was decreased independently of the form of treatment (P < 0.0001) (median relative reduction: group A 37.6%, group B 30.9%; difference not significant). Iodide excretion rose in both groups, without significant difference (group A 107%, group B 49%). There was hardly any change of the hyperthyroid score in both groups. There were no side effects.


CONCLUSIONS
Both forms of medication were equally efficacious and well tolerated in the treatment of euthyroid goitre.
Förster
G
G
Klinik und Poliklinik Innere Medizin, Endokrinologie und Stoffwechselerkrankungen, Johannes Gutenberg-Universität Mainz.
Krummenauer
F
F
Hansen
C
C
Beyer
J
J
Kahaly
G
G
D000328:Adult; D004311:Double-Blind Method; D004338:Drug Combinations; D004359:Drug Therapy, Combination; D005260:Female; D006043:Goiter, Endemic / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy*; D006801:Humans; D007454:Iodides / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D011446:Prospective Studies; D013961:Thyroid Gland / Q000000981:diagnostic imaging; D013963:Thyroid Hormones / Q000097:blood; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000008:administration & dosage* / Q000009:adverse effects; D013997:Time Factors; D014463:Ultrasonography
D004338:Drug Combinations; D007454:Iodides; D013963:Thyroid Hormones; D013972:Thyrotropin; D013974:Thyroxine
Individuell dosiertes Levothyroxin mit 150 micrograms Jodid versus 100 micrograms Levothyroxin kombiniert mit 100 micrograms Jodid. Eine randomisierte Doppelblindstudie.