Hyponatremia and seizures after bowel preparation: report of three cases

Dis Colon Rectum. 2005 Feb;48(2):393-6. doi: 10.1007/s10350-004-0778-6.


Oral sodium phosphate and sodium picosulfates/magnesium citrate are commonly used to evacuate the colon and rectum before colonoscopy or colorectal surgery. These substances, however, are known to cause electrolyte abnormalities. Seizures caused by electrolyte abnormalities associated with bowel preparation have only rarely been reported. We report the cases of three patients with no prior history of seizures, who had their first seizure associated with hyponatremia following ingestion of sodium phosphate or sodium picosulfates/magnesium citrate combination. Care must be taken with patients with a low seizure threshold and those with possible chronic sodium depletion, such as patients on thiazide diuretics, who are undertaking bowel preparation with oral sodium phosphate or sodium picosulfates/magnesium citrate combination.

Publication types

  • Case Reports

MeSH terms

  • Administration, Oral
  • Adult
  • Aged
  • Cathartics / administration & dosage
  • Cathartics / adverse effects*
  • Citric Acid / administration & dosage
  • Citric Acid / adverse effects*
  • Colonoscopy
  • Female
  • Humans
  • Hyponatremia / chemically induced*
  • Middle Aged
  • Organometallic Compounds / administration & dosage
  • Organometallic Compounds / adverse effects*
  • Phosphates / administration & dosage
  • Phosphates / adverse effects*
  • Seizures / chemically induced*
  • Solutions


  • Cathartics
  • Organometallic Compounds
  • Phosphates
  • Solutions
  • Citric Acid
  • magnesium citrate
  • sodium phosphate