TSH Normalization in Bariatric Surgery Patients After the Switch from L-Thyroxine in Tablet to an Oral Liquid Formulation.
Drug malabsorption is one of the potential troubles after bariatric surgery. Evidence for diminished levothyroxine (L-T4) absorption has been reported in patients after bariatric surgery.



This study reports 17 cases of hypothyroid patients [who were well replaced with thyroxine tablets (for >1 year) to euthyroid thyrotropin (TSH) levels before surgery (13 Roux-en-Y gastric bypasses (RYGB); 4 biliary pancreatic diversions (BPD))]. From 3 to 8 months after surgery, these patients had elevated TSH levels. Patients were then switched from oral tablets to a liquid L-T4 formulation (with the same dosage, 30 min before breakfast).



Two-three months after the switch, TSH was significantly reduced both in patients treated with RYGB, as in those treated with BPD, while FT4 and FT3 levels were not significantly changed (RYGB group, TSH μIU/mL: 7.58 ± 3.07 vs 3.808 ± 1.83, P < 0.001; BPD group, TSH μIU/mL: 8.82 ± 2.76 vs 3.12 ± 1.33, P < 0.01).



These results first show that liquid L-T4 could prevent the problem of malabsorption in patients with BPD and confirm those of previous studies in patients submitted to RYGB, suggesting that the L-T4 oral liquid formulation could circumvent malabsorption after bariatric surgery.
Department of Clinical and Experimental Medicine, University of Pisa, Via Savi 10, 56126, Pisa, Italy.
Poupak
P
Fallahi
Department of Clinical and Experimental Medicine, University of Pisa, Via Savi 10, 56126, Pisa, Italy.
Silvia Martina
SM
Ferrari
Department of Clinical and Experimental Medicine, University of Pisa, Via Savi 10, 56126, Pisa, Italy.
Stefania
S
Camastra
Department of Clinical and Experimental Medicine, University of Pisa, Via Savi 10, 56126, Pisa, Italy.
Ugo
U
Politti
Department of Clinical and Experimental Medicine, University of Pisa, Via Savi 10, 56126, Pisa, Italy.
Ilaria
I
Ruffilli
Department of Clinical and Experimental Medicine, Section of Endocrinology, University of Messina, Messina, Italy.
Roberto
R
Vita
Department of Human Pathology, University Hospital of Messina, Messina, Italy.
Giuseppe
G
Navarra
Department of Clinical and Experimental Medicine, Section of Endocrinology, University of Messina, Messina, Italy.
Salvatore
S
Benvenga
Department of Clinical and Experimental Medicine, University of Pisa, Via Savi 10, 56126, Pisa, Italy. alessandro.antonelli@med.unipi.it.
Alessandro
A
Antonelli
D000328:Adult; D050110:Bariatric Surgery / Q000009:adverse effects*; D004304:Dosage Forms; D005260:Female; D015390:Gastric Bypass; D006801:Humans; D007037:Hypothyroidism / Q000097:blood* / Q000188:drug therapy; D008286:Malabsorption Syndromes / Q000097:blood / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood* / Q000601:surgery; D013607:Tablets; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000008:administration & dosage* / Q000493:pharmacokinetics*
D004304:Dosage Forms; D013607:Tablets; D013972:Thyrotropin; D013974:Thyroxine
Bariatric surgery; Biliary pancreatic diversion; Hypothyroidism; Levothyroxine malabsorption; Liquid L-T4; Roux-en-Y gastric bypass