-5%
Paloset is used for the prevention and treatment of nausea and vomiting in the following conditions:
- Acute & delayed nausea and vomiting
- Uncontrolled nausea and vomiting
- Chemotherapy-induced nausea and vomiting (CINV):
- Acute CINV: Occurs on the day of chemotherapy treatment.
- Delayed CINV: Develops days after chemotherapy.
- Radiotherapy-induced nausea and vomiting (RINV)
- Post-operative & post-discharge nausea and vomiting (PONV & PDNV)
Palonosetron is a 5-HT3 receptor antagonist with a strong affinity for these receptors, which play a key role in nausea and vomiting.
- Chemotherapy-induced nausea and vomiting (CINV): Chemotherapy drugs trigger serotonin release in the intestines, which stimulates 5-HT3 receptors, initiating the vomiting reflex. Palonosetron blocks these receptors, preventing nausea and vomiting.
- Postoperative nausea and vomiting (PONV): Factors like anesthesia, surgery type, and individual patient sensitivity contribute to nausea and vomiting. Palonosetron works centrally and peripherally to prevent these effects.
Palonosetron primarily acts in the small intestine but may also work in the brain.
Pharmacokinetics
- Exhibits dose-proportional pharmacokinetics.
- Absorption & Distribution:
- Volume of distribution: 6.9-7.9 L/kg
- 62% of the drug binds to plasma proteins.
- Metabolism & Elimination:
- 50% metabolized into inactive metabolites via the liver (CYP2D6, CYP3A4, CYP1A2 enzymes).
- 40% excreted unchanged through the kidneys.
- Half-life: ~40 hours, providing prolonged 5-HT3 receptor binding and efficacy.