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Last reviewed: 13 Jan 2026
Last updated: 13 Jan 2026

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • muscle weakness
  • paraesthesia
  • back/leg pain
  • respiratory distress
  • speech problems
  • areflexia/hyporeflexia
  • facial weakness
  • bulbar dysfunction causing oropharyngeal weakness
  • extra-ocular muscle weakness
  • facial droop
  • diplopia
  • dysarthria
  • dysphagia
  • dysautonomia
  • pupillary dysfunction
  • ophthalmoplegia

Other diagnostic factors

  • ataxia
  • ptosis
  • altered level of consciousness

Risk factors

  • preceding viral illness
  • preceding bacterial infection
  • preceding arthropod-borne viral infection
  • hepatitis E infection
  • immunisation
  • cancer and lymphoma
  • immune checkpoint inhibitor or chimeric antigen receptor (CAR) T-cell immunotherapy
  • older age
  • HIV infection
  • COVID-19 infection
  • male sex

Diagnostic investigations

1st investigations to order

  • nerve conduction studies
  • lumbar puncture
  • LFTs
  • spirometry

Investigations to consider

  • anti-ganglioside antibody
  • serology
  • stool culture
  • HIV antibodies
  • spinal MRI
  • ultrasound imaging of peripheral nerves
  • Borrelia burgdorferi serology
  • cerebrospinal fluid (CSF) meningococcal polymerase chain reaction
  • CSF cytology
  • CSF angiotensin-converting enzyme
  • chest x-ray
  • CSF VDRL
  • CSF West Nile polymerase chain reaction

Treatment algorithm

Contributors

Authors

Saiju Jacob, MD, DPhil, MRCP (UK), FRCP (Lon), FAAN

Consultant Neurologist

Queen Elizabeth Neurosciences Centre

University Hospital Birmingham

Birmingham

UK

Disclosures

SJ has served as a paid international advisory board member or invited speaker for Alexion, Alnylam, ArgenX, Immunovant, Janssen, Merck, Novartis, Regeneron and UCB pharmaceuticals, is currently an expert panel member of the Myasthenia Gravis Consortium for Argenx pharmaceuticals. He has received speaker’s fees from Terumo BCT and Eisai pharmaceuticals. SJ declares that none of these are relevant to the current article.

Roshan Iqbal, MD, DM, MRCP (UK)

Neurology Specialist Registrar

Queen Elizabeth Neurosciences Centre

University Hospital Birmingham

Birmingham

UK

Disclosures

RI declares that he has no competing interests.

Acknowledgements

Prof Saiju Jacob would like to gratefully acknowledge Prof John B. Winer, Dr Michael T. Torbey, Dr Dhruvil J. Pandya, and Dr Prem A. Kandiah, previous contributors to this topic.

Disclosures

JBW, MTT, DJP, and PAK declare that they have no competing interests.

Peer reviewers

Long Davalos Loo, MD

​Assistant Professor of Neurology

University of Cincinnati

Cincinnati

OH

Disclosures

LDL declares that he has no competing interests.

Robert Hadden, FRCP, PhD

Consultant Neurologist

King's College Hospital

London

UK

Disclosures

RH has been paid by Baxter Healthcare Ltd for membership of its neurology advisory board, and is a co-author of several studies referenced in this topic.

Peer reviewer acknowledgements

BMJ Best Practice topics are updated on a rolling basis in line with developments in evidence and guidance. The peer reviewers listed here have reviewed the content at least once during the history of the topic.

Disclosures

Peer reviewer affiliations and disclosures pertain to the time of the review.

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

van Doorn PA, Van den Bergh PYK, Hadden RDM, et al. European Academy of Neurology/Peripheral Nerve Society guideline on diagnosis and treatment of Guillain-Barré syndrome. Eur J Neurol. 2023 Dec;30(12):3646-74.Full text  Abstract

Leonhard SE, Mandarakas MR, Gondim FAA, et al. Diagnosis and management of Guillain-Barré syndrome in ten steps. Nat Rev Neurol. 2019 Nov;15(11):671-83.Full text  Abstract

Hughes RA, Swan AV, van Doorn PA. Intravenous immunoglobulin for Guillain-Barré syndrome. Cochrane Database Syst Rev. 2014 Sep 19;(9):CD002063.Full text  Abstract

Hughes RA, Wijdicks EF, Barohn R, et al. Practice parameter: immunotherapy for Guillain-Barré syndrome: report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology. 2003 Sep 23;61(6):736-40.Full text  Abstract

Reference articles

A full list of sources referenced in this topic is available here.

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