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Levothyroxine (L-T4) treatment with coffee, or with water followed by coffee within a few minutes, results in poor TSH response in many patients. Thyroxine is worldwide suitable in tablets form but novel formulations in soft gel capsule or liquid formulation are now available.

Oral liquid levothyroxine treatment at breakfast: a mistake?
C Cappelli, I Pirola, E Gandossi, AM Formenti, M Castellano

Wie heeft ervaring met Tirosint?
Schildklierforum

Oral liquid l-Thyroxine (l-T4) may be better absorbed compared to l-T4 tablets following bariatric surgery
I Pirola, AM Formenti, E Gandossi, F Mittempergher, C Casella, B Agosti, C Cappelli

Oral liquid formulation of levothyroxine is stable in breakfast beverages and may improve thyroid patient compliance
A Bernareggi, E Grata, MT Pinorini, A Conti

Switching levothyroxine from the tablet to the oral solution formulation corrects the impaired absorption of levothyroxine induced by proton-pump inhibitors
R Vita, G Saraceno, F Trimarchi, S Benvenga

Design

We fortuitously observed an euthyroid patient who wrongly assumed liquid L-T4 with coffee at breakfast: after changing the assumption thirty minutes before breakfast, no change of TSH, fT4 and fT3 was observed. Once the first patient was identified, we identified additional stable euthyroid patients who assumed liquid L-T4 with coffee.

In Nederland
Volgens het College ter Beoordeling van Geneesmiddelen (CBG) zijn in Nederland nu ook zulke zachte capsules verkrijgbaar met levothyroxine natrium en de hulpstoffen gelatine, glycerol en gedemineraliseerd water. Een dergelijk middel is geregistreerd en heeft een handelsvergunning. Het gaat hier om Tirosint (productkenmerken en bijsluiter). Onduidelijk is of het middel al echt verkrijgbaar is.

Methods

Patients were recruited by searching our thyroid patients database. All patients on liquid L-T4 treatment were contacted by phone to find out if L-T4 was taken at breakfast. We identified fifty-four patients that were submitted to TSH, fT4 and fT3 evaluation, with the following indication to assume the same dosage of L-T4 half hour before breakfast. We checked again their TSH, fT4 and fT3 values, 3 and 6 months later.

Results

No significative difference of thyroid hormonal values was observed between patients who assumed L-T4 at breakfast and after 3 and 6 months of its assumption half hour before breakfast [TSH: 2.5 ± 1.1 vs 2.5 ± 1.1 and 2.4 ± 1.1 (mIU/L), respectively], [fT4: 12.4 ± 2.4 vs 12.5 ± 2.4 and 12.3 ± 2.1 (pg/mL), respectively] and [fT3: 3.4 ± 0.6 vs 3.4 ± 0.6 and 3.3 ± 0.5 (pg/mL), respectively].

Conclusion

Oral liquid L-T4 could remove the problem of L-T4 malabsorption by coffee observed with traditional tablets formulations.