Tenapanor (Xphozah) is used to lower serum phosphorus in adult dialysis patients and must be strictly used according to the dosage and administration instructions.

I. Dosage and Administration

1. Recommended Dose

(1) 30 mg twice daily, taken orally before meals.

(2) It is recommended to take before morning and evening meals.

2. Timing of Administration

(1) Take 5-10 minutes before meals for optimal effect (increases 24-hour fecal phosphorus excretion).

(2) Clinical trials administered the drug before the first meal and dinner.

3. Dose Adjustment

The physician may adjust the dose based on serum phosphorus levels and gastrointestinal tolerability; patients should not adjust the dose on their own.

4. Missed Dose

(1) If a dose is missed, skip that dose and take the next dose at the regularly scheduled time.

(2) Do not take two doses at the same time.

5. Special Reminder for Hemodialysis Patients

(1) Do not take the drug immediately before hemodialysis.

(2) The dose should be taken before the next meal after dialysis to avoid overlap of drug-induced diarrhea with the dialysis procedure.

II. Precautions for Use

1. Diarrhea Management

(1) Diarrhea is the most common side effect (incidence 43%-53%).

(2) Most cases are mild to moderate and may resolve over time or with dose reduction.

(4) Do not use stool softeners or laxatives while taking this medication.

2. Drug Interactions

(1) Enalapril and other OATP2B1 substrate drugs: Tenapanor may reduce their absorption, so monitor efficacy. However, for dialysis patients, no reduction in the starting dose of enalapril is needed.

(2) Sodium polystyrene sulfonate (potassium-lowering agent): Separate administration by at least 3 hours, as SPS can bind to many oral drugs.

3. Contraindications

(1) Children under 6 years of age.

(2) Patients with known or suspected mechanical gastrointestinal obstruction.

4. Recognizing Allergic Reactions

Post-marketing reports include pruritus, rash, and urticaria. If these occur, stop the drug and seek medical attention.

5. Storage Requirements

(1) Temperature: 20°C-25°C; brief excursions permitted between 15°C-30°C.

(2) Protect from moisture: Keep in original bottle with desiccant; do not remove the desiccant.

(3) Avoid transferring to other containers.

III. Healthy Lifestyle for Patients

1. Dietary Management

(1) Tenapanor itself has no specific food restrictions, but dialysis patients should continue to follow a low-phosphorus diet (e.g., limit nuts, organ meats, whole grains, foods with phosphorus additives).

(2) Taking before meals enhances efficacy; it is recommended to have fixed meal times.

2. Fluid Replacement

(1) Maintain fluid intake during diarrhea to prevent dehydration and hyponatremia.

(2) Oral rehydration solutions or light broths are suitable; avoid sugary drinks.

3. Regular Dialysis

(1) Complete hemodialysis treatments on time; do not delay or cancel dialysis due to medication.

(2) Coordinate medication and dialysis times (take before the next meal after dialysis).

4. Regular Monitoring

(1) Regularly check serum phosphorus, serum sodium, and renal function.

(2) Seek medical attention if persistent diarrhea, significant weight loss, fatigue, or rash occurs.

5. Medication Record

(1) Establish a medication schedule to avoid missed doses.

(2) When traveling or hospitalized, inform healthcare providers that you are taking Tenapanor to avoid omission or duplicate dosing.