Polystyrene sulfonate

Polystyrene sulfonates are a group of medications used to treat high blood potassium. Therapeutic effects generally appear hours to days after commencement of therapy. Common side effects include loss of appetite, gastrointestinal upset, constipation, and low blood calcium. Polystyrene sulfonates are given by mouth with a meal, or rectally by retention enema. Oral formulations often also contain the laxative sorbitol in order to lessen the risk of constipation which can be severe.

Polystyrene sulfonates are derived from polystyrene by the addition of sulfonate functional groups. Sodium polystyrene sulfonate was approved for medical use in the United States in 1958. A polystyrene sulfonate was developed in the 2000s to treat Clostridioides difficile associated diarrhea under the name Tolevamer, but it was never marketed.

Polystyrene sulfonates are also used in technical applications to remove potassium, calcium, and sodium from solutions.