calcium resonium
Last reviewed 01/2018
Calcium resonium is a polystyrene cation exchange resin which acts to remove excess potassium from the body by exchanging it for the cation ion (Ca++) in the resin. It is a relatively slow method of reducing serum potassium.
Onset of action is 2 - 12 hours; longer if given rectally.
The dose by mouth - or nasogastric tube is 15 grams 3 to 4 times daily in water, but not fruit juice which has a high potassium content.
In children, 0.3 to 0.6 grams per kg per dose is used, up to the adult dose, and given every 6 hours.
A rectal route may be used if oral administration is not possible. 30g in methylcellulose solution, retained if possible for 9 hours following which the colon should be irrigated to remove the resin. Retention for this length of time is difficult in practice. Given daily.
Calcium resonium enemas are available from pharmacies in the form of a powder which needs to reconstituted with water.
Caution: Constipation may develop, faecal impaction has been reported. In the event of clinically significant constipation, treatment should be discontinued until normal bowel movement is resumed.