Gefapixant Tablets (Lifnua) is a selective P2X3 receptor antagonist indicated for the treatment of refractory chronic cough.
Side Effects of Gefapixant Tablets (Lifnua)
Taste-Related Side Effects
Taste disturbances are the most common adverse reactions of gefapixant tablets, with a high incidence rate.
Dysgeusia (40.4%): Often presents as a bitter, metallic, or salty taste.
Ageusia (14.8%): Loss of taste.
Hypogeusia (13.0%): Reduced taste sensitivity.
Most taste disturbances occur within 9 days of starting treatment, are mostly mild to moderate in severity, and improve with continued treatment or after drug discontinuation.
Gastrointestinal Reactions
Common: Nausea, dry mouth.
Less common: Diarrhea, upper abdominal pain, dyspepsia, oral hypoesthesia, increased salivation, oral paresthesia, etc.
Side Effects in Other Systems
Nervous system: Dizziness.
Respiratory system: Cough, sore throat.
Metabolism and nutrition: Decreased appetite.
Infections: Upper respiratory tract infection.
Severe Side Effects of Gefapixant Tablets (Lifnua)
Impact on Renal Function
Gefapixant tablets are primarily excreted via the kidneys. Patients with renal impairment (especially those with eGFR < 30 mL/min/1.73m²) have significantly increased drug exposure, which may increase the risk of side effects.
Patients with severe renal impairment require dosage adjustment to once daily and regular monitoring of renal function.
Allergic Reactions
Contraindicated in patients with a history of hypersensitivity to any component of this product.
Due to the presence of a sulfonamide group, patients allergic to sulfonamide drugs may also experience cross-allergic reactions.
Precautions for Gefapixant Tablets (Lifnua)
Target Population and Diagnostic Prerequisites
This product is for symptomatic treatment, not etiological treatment.
Its use should only be considered after a comprehensive diagnosis (including medical history, occupation, environment, imaging studies, etc.) and trial of other treatments, if the cough persists.
Use in Special Populations
Pregnant women: Use only if the benefit outweighs the risk. Animal studies have shown that high doses may affect fetal weight.
Lactating women: Consider discontinuing the drug or breastfeeding, as the drug may be excreted in breast milk.
Children: Efficacy in patients under 18 years of age has not been established.
Elderly patients: Due to potential age-related decline in renal function, monitor renal function and adjust dosage as appropriate.
Drug Interactions
No significant interactions have been observed with proton pump inhibitors (e.g., omeprazole) or statins (e.g., pitavastatin).
This product is unlikely to affect the metabolism of other drugs via the CYP enzyme system.
Other Precautions
Storage: Store at room temperature. Shelf life is 48 months.
Administration method: Tablets must be removed from the PTP blister pack before taking to avoid accidental ingestion of the aluminum foil, which may cause esophageal injury.
Overdose management: Hemodialysis can partially remove the drug.
