FDA label bc2eae60-2bf3-2b2e-e053-2995a90af539

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Warnings cross-check#

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warnings and cautions

5 WARNINGS AND PRECAUTIONS Hypersensitivity reactions including anaphylaxis and bronchospasm: Discontinue ondansetron if suspected. Monitor and treat promptly per standard of care until signs and symptoms resolve. (5.1) QT interval prolongation and Torsade de Pointes: Avoid in patients with congenital long QT syndrome; monitor with electrocardiograms (ECGs) if concomitant electrolyte abnormalities, cardiac failure or arrhythmias, or use of other QT prolonging drugs. (5.2) Serotonin syndrome: Reported with 5-HT3 receptor antagonists alone but particularly with concomitant use of serotonergic drugs. If such symptoms occur, discontinue ondansetron and initiate supportive treatment. If concomitant use of ondansetron with other serotonergic drugs is clinically warranted, patients should be made aware of a potential increased risk for serotonin syndrome. (5.3) Masking of progressive ileus and/or gastric distention following abdominal surgery or chemotherapy-induced nausea and vomiting: Monitor for decreased bowel activity, particularly in patients with risk factors for gastrointestinal obstruction. (5.4) 5.1 Hypersensitivity Reactions Hypersensitivity reactions, including anaphylaxis and bronchospasm, have been reported in patients who have exhibited hypersensitivity to other selective 5-HT3 receptor antagonists. If hypersensitivity reactions occur, discontinue use of ondansetron; treat promptly per standard of care and monitor until signs and symptoms resolve [see Contraindications (4) ] . 5.2 QT Prolongation Electrocardiograms (ECG) changes including QT interval prolongation have been seen in patients receiving ondansetron. In addition, postmarketing cases of Torsade de Pointes have been reported in patients using ondansetron. Avoid ondansetron in patients with congenital long QT syndrome. ECG monitoring is recommended in patients with electrolyte abnormalities (e.g., hypokalemia or hypomagnesemia), congestive heart failure, bradyarrhythmias, or patients taking other medicinal products that lead to QT prolongation [see Clinical Pharmacology (12.2)] . 5.3 Serotonin Syndrome The development of serotonin syndrome has been reported with 5-HT3 receptor antagonists alone. 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 ondansetron alone has also been reported. The majority of reports of serotonin syndrome related to 5-HT3 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 ondansetron and other serotonergic drugs. If symptoms of serotonin syndrome occur, discontinue ondansetron and initiate supportive treatment. Patients should be informed of the increased risk of serotonin syndrome, especially if ondansetron is used concomitantly with other serotonergic drugs [see Drug Interactions (7.1) , Overdosage (10) ] . 5.4 Masking of Progressive Ileus and Gastric Distension The use of ondansetron in patients following abdominal surgery or in patients with chemotherapy-induced nausea and vomiting may mask a progressive ileus and/or gastric distension. Monitor for decreased bowel activity, particularly in patients with risk factors for gastrointestinal obstruction. Ondansetron is not a drug that stimulates gastric or intestinal peristalsis. It should not be used instead of nasogastric suction.

Adverse reactions cross-check#

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adverse reactions

6 ADVERSE REACTIONS The most common adverse reactions in adults for the: prevention of chemotherapy-induced (greater than or equal to 5%) are: headache, malaise/fatigue, constipation, diarrhea. (6.1) prevention of radiation-induced nausea and vomiting (greater than or equal to 2%) are: headache, constipation, and diarrhea. (6.1) prevention of postoperative nausea and vomiting (greater than or equal to 9%) are: headache and hypoxia. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Amneal Pharmaceuticals at 1-­877-835-5472 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in practice. The following adverse reactions have been reported in clinical trials of patients treated with ondansetron, the active ingredient of ondansetron. A causal relationship to therapy with ondansetron was unclear in many cases. Prevention of Chemotherapy-induced Nausea and Vomiting The most common adverse reactions reported in greater than or equal to 4% of 300 adults receiving a single 24-mg dose of ondansetron orally in 2 trials for the prevention of nausea and vomiting associated with highly emetogenic chemotherapy (cisplatin greater than or equal to 50 mg/m 2 ) were: headache (11%) and diarrhea (4%). The most common adverse reactions reported in 4 trials in adults for the prevention of nausea and vomiting associated with moderately emetogenic chemotherapy (primarily cyclophosphamide-based regimens) are shown in Table 3. Table 3. Most Common Adverse Reactions in Adultsa for the Prevention of Nausea and Vomiting Associated with Moderately Emetogenic Chemotherapy [Primarily Cyclophosphamide-based Regimens] Adverse Reaction Ondansetron 8 mg Twice Daily (n = 242) Placebo (n = 262) Headache 58 (24%) 34 (13%) Malaise/fatigue 32 (13%) 6 (2%) Constipation 22 (9%) 1 (<1%) Diarrhea 15 (6%) 10 (4%) Less Common Adverse Reactions Central Nervous System: Extrapyramidal reactions (less than 1% of patients). Hepatic: Aspartate transaminase (AST) and/or alanine transaminase (ALT) values exceeded twice the upper limit of normal in approximately 1% to 2% of 723 patients receiving ondansetron and cyclophosphamide-based chemotherapy in US clinical trials. The increases were transient and did not appear to be related to dose or duration of therapy. On repeat exposure, similar transient elevations in transaminase values occurred in some courses, but symptomatic hepatic disease did not occur. The role of cancer chemotherapy in these biochemical changes is unclear. Liver failure and death has been reported in cancer patients receiving concurrent medications, including potentially hepatotoxic cytotoxic chemotherapy and antibiotics. The etiology of the liver failure is unclear. Integumentary: Rash (approximately 1% of patients). Other (less than 2%): Anaphylaxis, bronchospasm, tachycardia, angina, hypokalemia, electrocardiographic alterations, vascular occlusive events, and grand mal seizures. Except for bronchospasm and anaphylaxis, the relationship to ondansetron is unclear. Prevention of Radiation-induced Nausea and Vomiting The most common adverse reactions (greater than or equal to 2%) reported in patients receiving ondansetron and concurrent radiotherapy were similar to those reported in patients receiving ondansetron and concurrent chemotherapy and were headache, constipation, and diarrhea. Prevention of Postoperative Nausea and Vomiting The most common adverse reactions reported in adults in trial(s) of prevention of postoperative nausea and vomiting are shown in Table 4. In these trial(s) patients were receiving multiple concomitant perioperative and postoperative medications in both treatment groups. Table 4. Most Common Adverse Reactions in Adultsa for the Prevention of Postoperative Nausea and Vomiting Adverse Reaction Ondansetron 16 mg as a Single Dose (n = 550) Placebo (n = 531) Headache 49 (9%) 27 (5%) Hypoxia 49 (9%) 35 (7%) Pyrexia 45 (8%) 34 (6%) Dizziness 36 (7%) 34 (6%) Gynecological disorder 36 (7%) 33 (6%) Anxiety/agitation 33 (6%) 29 (5%) Urinary retention 28 (5%) 18 (3%) Pruritus 27 (5%) 20 (4%) a Reported in greater than or equal to 5% of patients treated with ondansetron and at a rate that exceeded placebo. In a crossover study with 25 subjects, headache was reported in 6 subjects administered ondansetron ODT with water (24%) as compared with 2 subjects administered ondansetron ODT without water (8%). 6.2 Postmarketing Experience The following adverse reactions have been identified during post-approval use of ondansetron. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Cardiovascular Arrhythmias (including ventricular and supraventricular tachycardia, premature ventricular contractions, and atrial fibrillation), bradycardia, electrocardiographic alterations (including second-degree heart block, QT/QTc interval prolongation, and ST segment depression), palpitations, and syncope. Rarely and predominantly with intravenous ondansetron, transient ECG changes including QT interval prolongation have been reported. General Flushing. Rare cases of hypersensitivity reactions, sometimes severe (e.g., anaphylactic reactions, angioedema, bronchospasm, shortness of breath, hypotension, laryngeal edema, stridor) have also been reported. Laryngospasm, shock, and cardiopulmonary arrest have occurred during allergic reactions in patients receiving injectable ondansetron. Hepatobiliary Liver enzyme abnormalities. Lower Respiratory Hiccups. Neurology Oculogyric crisis, appearing alone, as well as with other dystonic reactions. Skin Urticaria, Stevens-Johnson syndrome, and toxic epidermal necrolysis. Eye Disorders Cases of transient blindness, predominantly during intravenous administration, have been reported. These cases of transient blindness were reported to resolve within a few minutes up to 48 hours.

adverse reactions table

<table border="1" cellspacing="0" cellpadding="0"><col width="2.55in"/><col width="2.55in"/><col width="2.55in"/><tbody><tr><td><paragraph><content styleCode="bold">Adverse Reaction </content></paragraph></td><td styleCode=" Lrule "><paragraph>Ondansetron <content styleCode="bold"> 8 mg Twice Daily (n = 242) </content></paragraph></td><td styleCode=" Lrule "><paragraph><content styleCode="bold">Placebo (n = 262) </content></paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Headache </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>58 (24%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>34 (13%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Malaise/fatigue </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>32 (13%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>6 (2%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Constipation </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>22 (9%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>1 (&lt;1%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Diarrhea </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>15 (6%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>10 (4%)</paragraph></td></tr></tbody></table>

adverse reactions table

<table border="1" cellspacing="0" cellpadding="0"><col width="234.9pt"/><col width="2.75in"/><col width="117.9pt"/><tbody><tr><td><paragraph><content styleCode="bold">Adverse Reaction</content></paragraph></td><td styleCode=" Lrule "><paragraph>Ondansetron <content styleCode="bold"> 16 mg as a Single Dose (n = 550) </content></paragraph></td><td styleCode=" Lrule "><paragraph><content styleCode="bold">Placebo (n = 531)</content></paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Headache </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>49 (9%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>27 (5%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Hypoxia </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>49 (9%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>35 (7%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Pyrexia </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>45 (8%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>34 (6%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Dizziness </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>36 (7%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>34 (6%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Gynecological disorder </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>36 (7%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>33 (6%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Anxiety/agitation </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>33 (6%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>29 (5%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Urinary retention </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>28 (5%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>18 (3%)</paragraph></td></tr><tr><td styleCode=" Toprule "><paragraph>Pruritus </paragraph></td><td styleCode=" Toprule Lrule "><paragraph>27 (5%)</paragraph></td><td styleCode=" Toprule Lrule "><paragraph>20 (4%)</paragraph></td></tr></tbody></table>