New FDA drug safety communication on Kayexalate

The US Food and Drug Administration is recommending that patients avoid taking the potassium-lowering drug sodium polystyrene sulfonate (Kayexalate, from Concordia Healthcare [(TSX: CXR]) at the same time as any other medicines taken by mouth.

A study found that sodium polystyrene sulfonate binds to many commonly prescribed oral medicines, decreasing the absorption and therefore effectiveness of those oral medicines. To reduce this likelihood, the FDA recommends separating the dosing of sodium polystyrene sulfonate from other orally administered medicines by at least 3 hours. It is updating the sodium polystyrene sulfonate drug labels to include information about this dosing separation.

Sodium polystyrene sulfonate is used to treat hyperkalemia, a serious condition in which the amount of potassium in the blood is too high. It works by binding with potassium in the intestines so it can be removed from the body. Potassium is a mineral that helps the body function properly. Too much potassium in the blood can cause problems with heart rhythm, which in rare cases can be fatal. Sodium polystyrene sulfonate is available as the brand name Kayexalate, as generic brands, and also as non-branded generics.