Tenapanor

Tenapanor is a medication used to treat irritable bowel syndrome with constipation (IBS-C) and chronic kidney disease (CKD) patients on dialysis to control serum phosphorus levels. It is a minimally absorbed sodium/hydrogen exchanger 3 (NHE3) inhibitor.

Mechanism of Action:

Tenapanor works primarily by inhibiting NHE3, which is found on the surface of intestinal cells. Blocking NHE3 reduces sodium absorption from the small intestine and colon. This, in turn, leads to increased water retention in the intestinal lumen, resulting in softer stools and more frequent bowel movements, benefiting patients with IBS-C.

In CKD patients on dialysis, tenapanor reduces serum phosphorus levels by inhibiting the uptake of phosphate in the gut. NHE3 inhibition reduces paracellular phosphate permeability, thus decreasing absorption of dietary phosphate.

Indications:

• Irritable Bowel Syndrome with Constipation (IBS-C)
• Hyperphosphatemia in adult patients with chronic kidney disease (CKD) on dialysis.

Dosage and Administration:

Dosage regimens vary depending on the indication and patient's individual needs. It is generally administered orally. Healthcare providers should be consulted for proper dosage instructions.

Contraindications:

Tenapanor is generally contraindicated in patients with a known or suspected mechanical gastrointestinal obstruction.

Adverse Effects:

Common side effects associated with tenapanor include diarrhea, abdominal distension, flatulence, and dizziness. Less common, but more serious side effects should be reported to a healthcare provider immediately.

Drug Interactions:

Clinically significant drug interactions may occur with tenapanor. Patients should inform their healthcare provider of all medications, supplements, and herbal remedies they are taking.

Pregnancy and Lactation:

The safety and efficacy of tenapanor in pregnant or breastfeeding women have not been fully established. Use during pregnancy and lactation should be carefully considered, weighing the potential benefits against the risks.

Pharmacokinetics:

Tenapanor is minimally absorbed systemically, with the majority of the drug remaining in the gastrointestinal tract.

Regulatory Approval:

Tenapanor has received regulatory approval from health authorities in various countries for the treatment of IBS-C and hyperphosphatemia in CKD patients on dialysis.