A cation exhange resin.
Kayexalate, brand of sodium polystyrene sulfonate is a benzene, diethenyl-polymer, with ethenylbenzene, sulfonated sodium salt.
Has an in vitro exchange capacity of approximately 3.1 mEq (in vivo approximately 1 mEq) of potassium per gram.
Sodium content is approximately 100 mg (4.1 mEq) per gram.
Can be administered orally or in an enema.
The exchange resin passes along the intestine when administered orally, or is retained in the colon after administration by enema.
Sodium ions are partially released and are replaced by potassium ions.
This action occurs primarily in the large intestine, which excretes potassium ions to a greater degree than does the small intestine.
The efficiency of this exchange is variable and unpredictable, but approximates the order of 33 percent.
Indicated for the treatment of hyperkalemia.
Oral 15-30 gm in 20% sorbitol, rectal 50 gm in 20% sorbitol.