One sip of water with LT-4 supplementation-a key to euthyroidism in Hashimoto's thyroiditis.

Purpose: Recommended pharmacotherapy for hypothyroidism in Hashimoto's thyroiditis (HT) is oral supplementation with levothyroxine (LT-4). However, serum thyrotropin (TSH) levels within normal range are not consistently achieved with LT-4 medication.

Patients And Methods: We report on 35 HT patients with LT-4 therapy in this retrospective evaluation. In general, we recommend that a maximum of two sips of water, which would then amount to < 50 mL, be ingested at the same time as LT-4. We report on follow up examinations measuring TSH and antibodies against thyroid peroxidase (TPOAb) after 6 months to five years.

Results: After median time of 643 days (range 98-1825) we found in 35 HT patients a statistical significant reduction of serum TSH (p < 0.001) and TPOAb (p = 0.006). The patients median body weight was 71 kg (range 48-98) and a daily LT-4 dosage was used with median 69.1 µg (range 25-150). This results in a daily LT-4 dose of median 1.01 µg/kg bodyweight (range 0.3-2.3).

Conclusions: The reduction of water ingestion to a maximum of two sips, which is <50 mL, combined with LT-4 supplementation helps to achieve euthyroidism in HT. In addition, it reduces the L-T4 medication dosage needed to lower TSH serum levels and decreases TPO antibodies in HT.