Tenapanor (Xphozah) is used to lower serum phosphorus in dialysis patients, with the most common side effect being diarrhea. Correctly identifying side effects, mastering mitigation methods, and storing the medication properly are crucial for safe use.
I. Side Effects of Tenapanor
1. Most Common Side Effect: Diarrhea
(1) Incidence up to 43%-53% in clinical trials.
(2) Mostly mild to moderate, may resolve over time or with dose reduction.
(3) Approximately 5% of patients experience severe diarrhea.
2. Diarrhea-Related Complications
(1) Dehydration and hyponatremia: incidence<1%.
(2) Severe or prolonged diarrhea can lead to significant fluid loss.
3. Post-Marketing Allergic Reactions
(1) Pruritus, rash, urticaria.
(2) Frequency unknown; caution warranted if they occur.
4. Other Potential Side Effects
Based on pharmacological mechanism, overdose may worsen gastrointestinal reactions such as bloating and abnormal defecation.
II. Ways to Alleviate Side Effects
1. Management Strategies for Diarrhea
(1) Mild to moderate diarrhea: usually self-resolving or improved by dose adjustment under medical guidance.
(2) Severe diarrhea: discontinue medication immediately and contact a doctor; do not continue taking.
(3) Do not use antidiarrheals or laxatives on your own: the label explicitly prohibits concomitant use with stool softeners or laxatives.
2. Prevention of Dehydration and Electrolyte Imbalance
(1) Ensure adequate fluid intake (e.g., oral rehydration solutions) during diarrhea.
(2) Monitor for signs of dehydration such as dizziness, dry mouth, and reduced urination.
(3) Regularly check electrolytes, especially serum sodium levels.
3. Management of Allergic Reactions
(1) If pruritus, rash, or urticaria occurs, stop the medication and seek medical attention.
(2) A doctor will assess whether it is a drug allergy and determine subsequent treatment.
4. Dose Adjustment Principles
(1) The physician may adjust the dose based on serum phosphorus levels and gastrointestinal tolerability.
(2) Patients should not adjust or discontinue the medication on their own.
III. Storage Conditions for Tenapanor
1. Temperature Requirements
(1) Store at 20°C to 25°C (68°F to 77°F).
(2) Excursions permitted between 15°C and 30°C (59°F to 86°F), compliant with USP controlled room temperature standards.
2. Moisture Protection
(1) Keep bottle cap tightly closed to prevent moisture ingress.
(2) Store in original container; do not remove the desiccant (silica gel canister) inside the bottle.
(3) The drug is hygroscopic; humid environments can cause degradation.
3. Packaging and Dispensing
(1) Use high-density polyethylene (HDPE) bottle with a child-resistant cap and induction-sealed aluminum foil liner.
(2) Do not transfer tablets to another container.
4. Light Protection and Others
(1) No special light protection required, but avoid high temperature and high humidity environments (e.g., bathroom).
(2) Do not use expired medication; dispose of according to local regulations.
