Thiamine
| Evidence Level: L3 | Predicted Indications: 10 |
Table of Contents
Thiamine: From Thiamine Deficiency to Hyperthyroidism
One-Sentence Summary
Thiamine (Vitamin B1) is an essential coenzyme classically used to correct thiamine deficiency states such as beriberi and Wernicke’s encephalopathy. The TxGNN model predicts it may have adjunctive value in Hyperthyroidism, specifically for correcting the secondary (relative) thiamine deficiency and associated cardiovascular dysfunction seen in this hypermetabolic state, with 1 completed clinical trial and 20 publications currently identified in support.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Thiamine (Vitamin B1) deficiency states — e.g. beriberi, Wernicke’s encephalopathy (based on known pharmacology; no licensed indication text was available in the Evidence Pack) |
| Predicted New Indication | Hyperthyroidism |
| TxGNN Prediction Score | 99.44% |
| Evidence Level | L3 |
| UK Market Status | Not Marketed |
| Number of Marketing Authorisations | 0 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data for this product is not available in the Evidence Pack. Based on known pharmacology, thiamine is converted in the body to thiamine pyrophosphate, an essential coenzyme for carbohydrate metabolism and the citric acid cycle, and is particularly important for tissues with high energy demand such as cardiac muscle and the nervous system.
Hyperthyroidism is a hypermetabolic state that increases thiamine turnover and utilisation, which can produce a relative or absolute thiamine deficiency. Clinically, this has been documented as hyperthyroidism-associated Wernicke’s encephalopathy and as high-output (“beriberi-like”) heart failure in thyrotoxic patients. On this basis, thiamine supplementation is not proposed as a treatment for hyperthyroidism itself, but as a corrective therapy for the secondary deficiency it induces, aiming to improve associated cardiovascular and neurological complications.
This mechanistic link is directly supported by a small completed pilot trial in patients with severe hyperthyroidism, together with a substantial body of case reports and older physiological studies describing thiamine–thyroid interactions. However, the evidence base currently consists mainly of small studies and case reports rather than confirmatory randomised trials.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrolment | Key Findings |
|---|---|---|---|---|
| NCT02767245 | Phase NA | Completed | 12 | Pilot study evaluating the prevalence of thiamine deficiency and improvement in cardiovascular function following thiamine supplementation in patients with severe hyperthyroidism (thyrotoxicosis is a hypermetabolic state associated with increased thiamine utilisation and deficiency). |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 9704251 | 1998 | Review | Drug Safety | Reviews treatment of nausea and vomiting in pregnancy, including thiamine supplementation to prevent Wernicke’s encephalopathy in hyperemesis-related thyrotoxic states. |
| 32983708 | 2020 | Case Report | Cureus | Wernicke’s encephalopathy associated with transient gestational hyperthyroidism and hyperemesis gravidarum, resolved with thiamine treatment. |
| 18026802 | 2008 | Case Report | Journal of General Internal Medicine | Describes thyrotoxicosis-associated Wernicke’s encephalopathy due to thiamine deficiency. |
| 26567494 | 2015 | Case Report | Critical Care Nursing Clinics of North America | High-output heart failure caused by thyrotoxicosis and beriberi (thiamine deficiency), highlighting shared haemodynamic mechanisms. |
| 21064291 | 1946 | Basic Science | Federation Proceedings | Early physiological study of the effect of thiamine deficiency and hyperthyroidism on cardiac muscle ATP content and activity in rats. |
| 25148818 | 2014 | Case Report | Endocrine Practice | Case of gestational thyrotoxicosis associated with Wernicke’s encephalopathy. |
| 22436368 | 2013 | Case Report | Neurología (Barcelona) | Wernicke’s encephalopathy secondary to hyperthyroidism and ingestion of thiaminase-rich products. |
| 36176825 | 2022 | Case Report | Cureus | Uncommon presentation of hyperthyroidism culminating in neurological consequences attributable to thiamine deficiency. |
| 36593922 | 2023 | Case Report | Radiology Case Reports | Uncommon presentation of Wernicke-Korsakoff syndrome in pregnancy in a patient with pre-gestational hyperthyroidism. |
| 7416185 | 1980 | Case Series | American Journal of Medicine | Reappearance of beriberi heart disease in Japan; 23 cases illustrating thiamine-deficiency cardiac disease relevant to hypermetabolic states. |
UK Market Information
No MHRA marketing authorisation records were identified in the Evidence Pack for this product (0 licences, market status: Not Marketed). Thiamine-containing licensed medicines for deficiency states are separately available in the UK; prescribers should consult the current MHRA Products database and BNF for authorised thiamine products, formulations and licensed indications.
Safety Considerations
Please refer to the SmPC and BNF for safety information. Report suspected adverse reactions via the Yellow Card Scheme.
Conclusion and Next Steps
Decision: Hold
Rationale: The mechanistic rationale is plausible — hyperthyroidism increases thiamine turnover and can precipitate a correctable secondary deficiency — but supporting evidence is currently limited to one small completed pilot trial (n=12, no comparator/phase designation) and a body of case reports/case series rather than confirmatory randomised controlled trials. This corresponds to Evidence Level L3, insufficient on its own to support a “Go” decision.
To proceed, the following is needed:
- Detailed mechanism of action (MOA) data (currently a Blocking/High-severity data gap)
- TFDA/MHRA labelling data on warnings and contraindications (currently a Blocking data gap for safety pre-screening)
- A prospective randomised trial confirming clinical benefit (not just deficiency correction) in hyperthyroid patients, ideally stratified by baseline thiamine status
- Clarification of the target population — whether this indication applies broadly to hyperthyroidism or specifically to patients with documented/suspected thiamine deficiency (e.g. severe thyrotoxicosis, hyperemesis gravidarum, poor nutritional intake)
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.