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Myopathies Treatment & Management

  • Author: Courtney A Bethel, MD, MPH; Chief Editor: Barry E Brenner, MD, PhD, FACEP  more...
Updated: Dec 27, 2015

Emergency Department Care

Respiratory insufficiency, associated cardiomyopathy, heart block, and aspiration may result from severe myopathy. Management is supportive.

Patients with rhabdomyolysis warrant inpatient and critical care admission to manage potentially life-threatening renal complications and hyperkalemia.

In patients with hypokalemic periodic paralysis, IV or oral potassium replacement may be indicated. Note the following:

  • Swallowing usually is not impaired, and oral supplementation may blunt the acute attack.
  • IV potassium should be given cautiously, if used at all.
  • Attacks will resolve spontaneously within 4-24 hours, and hyperkalemia may result if potassium supplementation has been excessive.
  • Spironolactone and acetazolamide are useful for prophylaxis of attacks.

In patients with hyperkalemic periodic paralysis, attacks are often so brief that no therapy is needed. Note the following:

  • Some patients find that carbohydrate loading at the onset of symptoms may lessen the attack.
  • Glucose and insulin may be useful in lowering serum potassium levels. Kayexalate has not been shown to be effective.


Consultation with one or more of the following services may be useful:

  • Neurologist
  • Rheumatologist
  • Infectious disease specialist
Contributor Information and Disclosures

Courtney A Bethel, MD, MPH Clinical Assistant Professor, Department of Emergency Medicine, Mercy Catholic Medical Center, Drexel University School of Medicine

Courtney A Bethel, MD, MPH is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Paul Blackburn, DO, FACOEP, FACEP Attending Physician, Department of Emergency Medicine, Maricopa Medical Center

Paul Blackburn, DO, FACOEP, FACEP is a member of the following medical societies: American College of Emergency Physicians, Arizona Medical Association, American College of Osteopathic Emergency Physicians, American Medical Association

Disclosure: Nothing to disclose.

Chief Editor

Barry E Brenner, MD, PhD, FACEP Professor of Emergency Medicine, Professor of Internal Medicine, Program Director for Emergency Medicine, Case Medical Center, University Hospitals, Case Western Reserve University School of Medicine

Barry E Brenner, MD, PhD, FACEP is a member of the following medical societies: Alpha Omega Alpha, American Heart Association, American Thoracic Society, Arkansas Medical Society, New York Academy of Medicine, New York Academy of Sciences, Society for Academic Emergency Medicine, American Academy of Emergency Medicine, American College of Chest Physicians, American College of Emergency Physicians, American College of Physicians

Disclosure: Nothing to disclose.

Additional Contributors

Jerry R Balentine, DO, FACEP, FACOEP Vice President, Medical Affairs and Global Health, New York Institute of Technology; Professor of Emergency Medicine, New York Institute of Technology College of Osteopathic Medicine

Jerry R Balentine, DO, FACEP, FACOEP is a member of the following medical societies: American College of Emergency Physicians, New York Academy of Medicine, American College of Osteopathic Emergency Physicians, American Association for Physician Leadership, American Osteopathic Association

Disclosure: Nothing to disclose.

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