Tenapanor is primarily used in the treatment of irritable bowel syndrome with constipation (IBS-C). It works by inhibiting the sodium/hydrogen exchanger 3 (NHE3) in the gastrointestinal tract, which reduces sodium absorption and increases water secretion into the intestines. This mechanism helps to soften stools and promote bowel movements, alleviating constipation. Additionally, Tenapanor is also utilized in managing hyperphosphatemia in patients with chronic kidney disease on dialysis. By reducing phosphate absorption in the gut, it helps control elevated phosphate levels, which is crucial for preventing complications such as bone disorders and cardiovascular issues in these patients. Its targeted action in the intestines minimizes systemic absorption, reducing the risk of side effects.