Levothyroxine treatment and gastric juice pH in humans: the proof of concept
Open accessAbstract
PURPOSE: Despite the absorption of oral thyroxine (T4) occurs in the small bowel, several patients with gastric disorders show an increased need for T4. In vitro evidence suggested that medium pH variations interfere with T4 dissolution. This study was aimed at finding the proof of concept of a direct relationship between the minimal effective dose of T4 and the actual gastric juice pH. PATIENTS AND METHODS: Among 311 consecutively thyroxine-treated patients, 61 bearing Hashimoto's thyroiditis (52 F/9 M; median age = 51 years) who complained persistent dyspepsia and/or upper abdominal symptoms following a noninvasive workup for gastrointestinal disorders, underwent EGDS with multiple biopsies and gastric juice pH measurement. All patients accepted to take thyroxine in fasting conditions, abstaining from eating or drinking for one hour. RESULTS: Thyroxine requirement increased along with the rising gastric pH (ρ = 0.4229; p = 0.0007). A multivariate analysis revealed that gastric pH was, beside body mass index, the far more important independent variable in determining the effective dose of T4 (p = 0.001). The ROC curve revealed that the pH threshold for an increased thyroxine requirement was at 2.28, being the AUC by 78%. Subdividing patients by the histologic findings, it appeared a significant increase (p = 0.0025) along with the progressive damage of gastric mucosa. CONCLUSION: The in vivo measurement of gastric pH highlighted its key role in determining the minimal effective dose of oral T4 and may explain the interference of food, of some drugs and gut disorders on levothyroxine treatment.
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
Doses of levothyroxine of approximately 1.3-1.5 μg/kg/day were reported to be sufficient in control subjects positively devoid of comorbidity or drug interference.
“Doses of levothyroxine of approximately 1.3–1.5 μg/kg/day were reported to be sufficient in control subjects positively devoid of comorbidity or drug interference (49).”
From ETA guidelines for the use of levothyroxine sodium preparations in monotherapy to optimize the treatment of hypothyroidism (2025) · cites this paper as [49]
A study measuring gastric pH in vivo showed a direct correlation between increasing gastric pH and the patient need for oral thyroxine.
“Indeed, a study measuring the gastric pH in vivo showed a direct correlation between the increasing gastric pH and the patient need for oral thyroxine (49).”
From ETA guidelines for the use of levothyroxine sodium preparations in monotherapy to optimize the treatment of hypothyroidism (2025) · cites this paper as [49]
Presence of an acidic environment in the stomach enables disaggregation and dissolution of tablet formulations, thus enhancing LT4 absorption at intestinal level.
“The presence of an acidic environment in the stomach enables the disaggregation and dissolution of tablet formulations to occur (49), thus enhancing LT4 absorption at the intestinal level.”
From ETA guidelines for the use of levothyroxine sodium preparations in monotherapy to optimize the treatment of hypothyroidism (2025) · cites this paper as [49]
The LT4 requirement increased with increasing gastric pH (P = .0007) in a retrospective study.
“More recently, direct in vivo proof for the role of gastric juice pH on LT4 absorption was provided by Virili et al in a retrospective study (17). The LT4 requirement increased with the increasing gastric pH (P = .0007).”
From Levothyroxine: conventional and novel drug delivery formulations. (2023) · cites this paper as [17]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
The citation lists haven’t been fetched yet
References 63 · Cited by 22
Research works printed but not linked: 1
- [22]Khraisha OS Al-Madani MM Peiris AN Paul TK Gastroparesis a novel cause of persistent thyroid stimulating hormone elevation in hypothyroidism J. LA State Med. Soc. 2015 167 2 47 49 25978052
- Authors
- Virili, C., Bruno, G., Santaguida, M. G., Gargano, L., Stramazzo, I., De Vito, C., Cicenia, A., Scalese, G., Porowska, B., Severi, C., & Centanni, M.
- Affiliations
- Sapienza University of Rome (IT)
- Corresponding author
- Centanni, Marco
- ORCID
- Venue
- Endocrine
- Published
- 2022-04-27
- Volume
- 77
- Issue
- 1
- Pages
- 102-111
- ISSN
- 0969-711X (ISSN-L)
- 1559-0100
- PMC
- PMC9242941
- OpenAlex
- W4225091021
- Cited by
- 22
- References
- 63
- Citations by year
- 2026: 3 · 2025: 3 · 2024: 10 · 2023: 2 · 2022: 4
- FWCI
- 3.52
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Locations
- Endocrine (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- IRIS Research product catalog (Sapienza University of Rome) (submittedVersion, cc-by)
- Topics
- Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Thyroid Disorders and Treatments
- Health Sciences › Medicine › Surgery › Thyroid and Parathyroid Surgery
- Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Thyroid Cancer Diagnosis and Treatment
- Keywords
- levothyroxine, gastric juice pH, thyroid hormone absorption, Hashimoto's thyroiditis, dyspepsia, gastric mucosal injury, body mass index
- MeSH terms
- Gastric Juice, Humans, Hydrogen-Ion Concentration, Middle Aged, Thyroxine, Hashimoto Disease
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
