sodium polystyrene sulfonate (Kalexate, Kayexalate, Kionex, SP) (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

Large oral doses have been reported to cause fecal impaction in the elderly, while large rectal doses have caused fecal impaction in children.

Colonic necrosis is one of the most serious side effects reported with rectal administration of sodium polystyrene sulfonate.

Rare but serious side effects are:




  • Oral suspension: 15 g/60 ml
  • Oral powder for suspension: 454 g
  • Rectal suspension: 15 g/60 ml

STORAGE: This medication should be stored at room temperature, between 15 C to 30 C (59 F to 86 F).


  • Oral dosage: Adults: The usual recommended dose is 15 g administered 1 to 4 times per day.
  • Oral dosage: Pediatrics: The usual recommended dose is 1 g/kg administered by mouth every 6 hours as needed.
  • Rectal dosage: Adults: The usual recommended dose is 30 to 50 g administered rectally every 1-2 hours initially, followed by repeat doses every 6 hours if needed.
  • Rectal dosage: Pediatrics: The usual recommended dose is 1 g/kg administered rectally every 6 hours as needed.


Cation-donating antacids or laxatives may reduce the effectiveness of sodium polystyrene sulfonate when given concomitantly. Examples of cation-donating antacids and laxatives include:

  • aluminum hydroxide,
  • calcium carbonate (Caltrate 600, Os-Cal 500, Tums Extra, Tums Chewy Delight, and Many Others),
  • magnesium carbonate,
  • magnesium citrate, and
  • magnesium hydroxide.

Sodium polystyrene sulfonate should be used cautiously with digoxin (Lanoxin) since sodium polystyrene sulfonate-induced hypokalemia (low blood potassium levels) may increase the risk of cardiac toxicity (heart rhythm abnormalities) associated with digoxin.

Concomitant use of sorbitol (Ora-Blend, Ora-Blend SF, Numoisyn Lozenges, Saliva Substitute) with sodium polystyrene sulfonate may cause colonic necrosis. Therefore, use of this combination treatment is not recommended.

Medically Reviewed by a Doctor on 12/15/2014

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