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Vitamin B1 deficiency

Last reviewed: 6 Apr 2025
Last updated: 03 Sep 2021

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • ocular abnormalities (Wernicke encephalopathy)
Full details

Other diagnostic factors

  • confusion (Wernicke encephalopathy)
  • ataxia (Wernicke encephalopathy)
  • fatigue
  • muscle aches
  • incessant crying (infantile beri-beri)
  • anorexia (infantile beri-beri)
  • bulging fontanelle (infantile beri-beri)
  • dyspnea (wet beriberi)
  • orthopnea (wet beriberi)
  • tachycardia (wet beriberi)
  • peripheral cyanosis (wet beriberi)
  • peripheral edema (wet beriberi)
  • decreased sensation (dry beriberi)
  • reduced tendon reflexes (dry beriberi)
  • muscle weakness (dry beriberi)
  • muscle wasting (dry beriberi)
Full details

Risk factors

  • chronic alcohol excess
  • malnutrition
  • staple diet of polished rice
  • age <1 year in endemic thiamine deficient region
  • refeeding/total parenteral nutrition
  • hyperemesis gravidarum
  • obesity
  • recurrent vomiting/chronic diarrhoea
  • gastrointestinal surgery
  • magnesium deficiency
  • HIV infection/AIDS
  • cancer and chemotherapy
  • thiaminase- and thiamine antagonist-containing diet
  • genetic mutation
Full details

Diagnostic tests

1st tests to order

  • erythrocyte thiamine pyrophosphate
  • arterial blood gas
  • lactate
  • thyroid function tests
Full details

Tests to consider

  • MRI brain
Full details

Treatment algorithm

INITIAL

at-risk asymptomatic hospitalized adults

outpatient on alcohol withdrawal program

ACUTE

symptomatic adults

symptomatic children and infants

Contributors

Authors

Jennifer Logue, MBChB, MRCP, MD, FRCPath
Jennifer Logue

Reader and Honorary Consultant in Metabolic Medicine

Lancaster University Medical School

Lancaster University

Lancaster

UK

Disclosures

JL declares that she has no competing interests.

Mike Lean, MA, MB, BChir, MD, MRCP, FRCPS, FRCP
Mike Lean

Professor of Human Nutrition

University of Glasgow

Glasgow

Scotland

UK

Disclosures

ML declares that he has no competing interests.

Peer reviewers

William Marshall, MA, MB, BS, PhD, MSc, FRCP, FRCPath, FRCPEdin, FSB

Emeritus Reader in Clinical Biochemistry

King's College London

Clinical Director of Pathology

The London Clinic

London

UK

Disclosures

WM declares that he has no competing interests.

Linda Edwards, MD

Chief and Associate Professor of Medicine

Division of General Internal Medicine

Associate Chairman

Department of Medicine

University of Florida College of Medicine

Jacksonville

FL

Disclosures

LE declares that she has no competing interests.

Martin Crook, BSc, MB, BS, MA, PhD, FRCPath, FRCPI, FRCP

Consultant Chemical Pathologist

Guy's Hospital

London

UK

Disclosures

MC declares that he has no competing interests.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

Whitfield KC, Bourassa MW, Adamolekun B, et al. Thiamine deficiency disorders: diagnosis, prevalence, and a roadmap for global control programs. Ann N Y Acad Sci. 2018 Oct;1430(1):3-43.Full text  Abstract

World Health Organisation, United Nations High Commissioner for Refugees. Thiamine deficiency and its prevention and control in major emergencies. 1999 [internet publication].Full text

Galvin R, Bråthen G, Ivashynka A, et al. Guidelines for diagnosis, therapy and prevention of Wernicke encephalopathy. Eur J Neurol. 2010 Dec;17(12):1408-18.Full text  Abstract

World Health Organization. The management of nutrition in major emergencies. 2000 [internet publicaton].Full text

Day E, Bentham PW, Callaghan R, et al. Thiamine for prevention and treatment of Wernicke-Korsakoff Syndrome in people who abuse alcohol. Cochrane Database Syst Rev. 2013 Jul 1;(7):CD004033.Full text  Abstract

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.
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  • Guidelines

    • Clinical Practice Guidelines for the Perioperative Nutrition, Metabolic, and Nonsurgical Support of Patients Undergoing Bariatric Procedures – 2019 Update
    • ESPEN guideline on clinical nutrition in the intensive care unit
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