Muscle cramps

Last reviewed: 23 Aug 2023
Last updated: 13 Apr 2023



History and exam

Key diagnostic factors

  • concurrent hemodialysis (organic cause)
  • cirrhosis (organic cause)
  • pregnancy (idiopathic cramp)
  • strenuous exercise (idiopathic cramp)
  • medication use (idiopathic cramp)
  • nocturnal onset (idiopathic cramp)
  • gastrocnemius muscle involvement, with or without foot involvement (idiopathic cramp)
  • duration <10 minutes (idiopathic cramp)
  • unilateral (idiopathic cramp)
  • precipitation by both trivial movements and forceful contractions (idiopathic cramp)
  • visible or palpable muscular knotting
  • good response to passive/active stretching (idiopathic cramp)
  • normal neurologic exam (idiopathic cramp)
  • normal general physical exam (idiopathic cramp)
  • other local muscle involvement (neuromuscular disease cramp)
  • widespread muscle cramps (lower motor neuron disease)
  • duration >10 minutes (organic cause)
  • abnormal neurologic exam (organic cause)
  • abnormal musculoskeletal exam (organic cause)
More key diagnostic factors

Other diagnostic factors

  • signs of a chronic medical condition (organic cause)
Other diagnostic factors

Risk factors

  • pregnancy
  • strenuous exercise
  • hemodialysis
  • cirrhosis
  • imatinib
  • beta-blockers with intrinsic sympathomimetic activity
  • age >60 years
  • female sex
  • family history of cramp
  • statins
  • other agents
  • hypoglycemia in patients with diabetes mellitus
  • chronic diseases
  • home parenteral nutrition
More risk factors

Diagnostic investigations

1st investigations to order

  • clinical diagnosis
More 1st investigations to order

Investigations to consider

  • serum or urine hCG
  • fasting serum metabolic panel
  • thyroid-stimulating hormone (TSH)
  • HbA1c
  • serum liver function tests
  • prothrombin time (PT) and INR
  • serum myoglobin and urinalysis
  • serum creatine kinase (CK)-MM
  • serum alpha-tocopherol (vitamin E)
  • serum zinc
  • EMG
  • nerve conduction studies
  • serum aldolase
  • muscle biopsy
  • genetic studies
More investigations to consider

Treatment algorithm


idiopathic cramps


hypoglycemia-associated in diabetes mellitus




multiple sclerosis- or lower motor neuron disease-associated

familial syndrome-associated




Michael Rubin, MD, FRCP(C)

Professor of Clinical Neurology

Weill Cornell Medical College

Attending Neurologist

Director, Neuromuscular Service and EMG Laboratory

New York Presbyterian Hospital

New York



MR states that he has no competing interests.


Dr Michael Rubin would like to gratefully acknowledge Dr Justin Mhoon and Dr David R.P. Guay, previous contributors to this topic. JM declares that he has no competing interests. DRPG is an author of a reference cited in this topic.

Peer reviewers

Timothy M. Miller, MD, PhD

Assistant Professor of Neurology

Department of Neurology

Washington University School of Medicine

St. Louis



TMM is an author of a reference cited in this topic.

Sami Khella, MD


Department of Neurology

Penn Presbyterian Medical Center

University of Pennsylvania Health System




SK declares that he has no competing interests.

Felicity Goodyear-Smith, MB CHB, DipObs, MGP, FRNZCGP, MFFLM, RCP

Professor and Goodfellow Postgraduate Chair

Department of General Practice & Primary Health Care

University of Auckland


New Zealand


FG-S declares that she has no competing interests.

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