Palonosetron Dexamethasone

Ondansetron is one of a group of 5HT3-receptor antagonists currently available in the UK, which also includes granisetron, tropisetron, dolasetron and palonosetron. Dexamethasone is a corticosteroid. Ranitidine is a histamine-2 (H2)-receptor antagonist. 

The UK manufaeturer notes that, in a population pharmaeokinetie analysis, enzyme indueers (dexamethasone and rifampicin) had no effect on palonosetron clearance. No palonosetron dose adjustment is likely to be necessary when given with these drugs. 

Aapro M, Fabi A, Nole F, Medici M, Steger G, Bachmann C, Roncoroni S, Roila F. Double-blind, randomised, controlled study of the efficacy and tolerability of palonosetron plus dexamethasone for 1 day with or without dexamethasone on days 2 and 3 in the prevention of... 

A 43-year-old woman with breast cancer and no history of seizures was scheduled to undergo chemotherapy with cyclophosphamide, 5-fluorouracil, and epirubicin and to receive antiemetic treatment with intravenous dexamethasone 8 mg and palonosetron 0.25 mg. During the fourth cycle of chemotherapy, she developed a generalized tonic-clonic seizure, which lasted 8 minutes and was followed by a period of drowsiness. She was given intravenous diazepam 10 mg and a saline infusion. Detailed investigations, including brain CT scan, did not reveal abnormalities, and she recovered completely. 

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