exercise associated hyponatraemia (EAH)

Last reviewed 01/2018

  • definition of exercise-associated hyponatraemia (EAH):
    • hyponatremia (less than the laboratory reference range usually < 135mmol Na+) occurring during or up to 24 hours of prolonged exertion (usually > 4 hrs duration) (1)

EAH should be classified using the same clinical criteria as any acute or rapid onset hyponatremia

  • most important factor is determining the presence or absence of clinical signs and symptoms: specifically neurological manifestations
  • in general, the lower the [Na+] the more severe the neurological signs and symptoms
    • however, individual variability is great and the numerical value of [Na+] is not a reliable predictive index of the clinical severity of hyponatremia, including EAH

Contributors (September 2010):

  • Dr Volker Scheer (GP Locum), Dr Andrew Murray (Marathon Medical Services)

Reference: