PALONOSETRON Drug Interactions: What You Need to Know

INTERACTIONS Palonosetron is eliminated from the body through both renal excretion and metabolic pathways with the latter mediated via multiple CYP enzymes. Further in vitro studies indicated that palonosetron is not an inhibitor of CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2D6, CYP2E1 and CYP3A4/5 (CYP2C19 was not investigated) nor does it induce the activity of CYP1A2, CYP2D6, or CYP3A4/5. Therefore, the potential for clinically significant drug interactions with palonosetron appears to be low. Serotonin syndrome (including altered mental status, autonomic instability, and neuromuscular symptoms) has been described following the concomitant use of 5-HT 3 receptor antagonists and other serotonergic drugs, including selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs) [ see Warnings and Precautions ( 5.2 ) ]. Coadministration of 0.25 mg I.V. palonosetron and 20 mg I.V. dexamethasone in healthy subjects revealed no pharmacokinetic drug-interactions between palonosetron and dexamethasone. In an interaction study in healthy subjects where palonosetron 0.25 mg (I.V. bolus) was administered on day 1 and oral aprepitant for 3 days (125 mg/80 mg/80 mg), the pharmacokinetics of palonosetron were not significantly altered (AUC: no change, C max : 15% increase). A study in healthy volunteers involving single-dose I.V. palonosetron (0.75 mg) and steady state oral metoclopramide (10 mg four times daily) demonstrated no significant pharmacokinetic interaction. In controlled clinical trials, Palonosetron Hydrochloride Injection has been safely administered with corticosteroids, analgesics, antiemetics /antinauseants, antispasmodics and anticholinergic agents. Palonosetron did not inhibit the antitumor activity of the five chemotherapeutic agents tested (cisplatin, cyclophosphamide, cytarabine, doxorubicin and mitomycin C) in murine tumor models. The potential for clinically significant drug interactions with palonosetron appears to be low ( 7 )

Palonosetron Hydrochloride Injection is contraindicated in patients known to have hypersensitivity to the drug or any of its components. [ see Adverse Reactions ( 6.2 ) ].

Palonosetron Hydrochloride

Injection is contraindicated in patients known to have hypersensitivity to the drug or any of its components ( 4 )

5.

Warnings And Precautions

Hypersensitivity reactions, including anaphylaxis and anaphylactic shock : reported in patients with or without known hypersensitivity to other selective 5-HT 3 receptor antagonists. If symptoms occur, discontinue Palonosetron Hydrochloride Injection and initiate appropriate medical treatment. ( 5.1 ) Serotonin syndrome : reported with 5-HT 3 receptor antagonists alone, but particularly with concomitant use of serotonergic drugs. ( 5.2 , 7.1 )

5.1 Hypersensitivity Reactions Hypersensitivity reactions, including anaphylaxis and anaphylactic shock, have been reported with administration of Palonosetron Hydrochloride Injection <span class="opacity-50 text-xs">[see Adverse Reactions ( 6.2 )]</span>. These reactions occurred in patients with or without known hypersensitivity to other 5-HT 3 receptor antagonists. If hypersensitivity reactions occur, discontinue Palonosetron Hydrochloride Injection and initiate appropriate medical treatment. Do not reinitiate Palonosetron Hydrochloride Injection in patients who have previously experienced symptoms of hypersensitivity <span class="opacity-50 text-xs">[see Contraindications ( 4 )]</span>.

5.2 Serotonin Syndrome The development of serotonin syndrome has been reported with 5-HT 3 receptor antagonists. Most reports have been associated with concomitant use of serotonergic drugs (e.g., selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors, mirtazapine, fentanyl, lithium, tramadol, and intravenous methylene blue). Some of the reported cases were fatal. Serotonin syndrome occurring with overdose of another 5-HT 3 receptor antagonist alone has also been reported. The majority of reports of serotonin syndrome related to 5-HT 3 receptor antagonist use occurred in a post-anesthesia care unit or an infusion center. Symptoms associated with serotonin syndrome may include the following combination of signs and symptoms: mental status changes (e.g., agitation, hallucinations, delirium, and coma), autonomic instability (e.g., tachycardia, labile blood pressure, dizziness, diaphoresis, flushing, hyperthermia), neuromuscular symptoms (e.g., tremor, rigidity, myoclonus, hyperreflexia, incoordination), seizures, with or without gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). Patients should be monitored for the emergence of serotonin syndrome, especially with concomitant use of Palonosetron Hydrochloride Injection and other serotonergic drugs. If symptoms of serotonin syndrome occur, discontinue Palonosetron Hydrochloride Injection and initiate supportive treatment. Patients should be informed of the increased risk of serotonin syndrome, especially if Palonosetron Hydrochloride Injection is used concomitantly with other serotonergic drugs <span class="opacity-50 text-xs">[see Drug Interactions ( 7.1 )]</span> .