• IV, PO: Prevention of nausea and vomiting associated with highly or moderately emetogenic chemotherapy.
• Prevention of postoperative nausea and vomiting.
• PO: Prevention of nausea and vomiting associated with radiation therapy.

Contraindicated in:

• Hypersensitivity
• Orally disintegrating tablets contain aspartame and should not be used in patients with phenylketonuria
• Congenital long QT syndrome
• Concurrent use of apomorphine.

Use Cautiously in:

• Hepatic impairment
• Abdominal surgery (may mask ileus)
• Phenylketonuria (orally disintegrating tablets contain phenylalanine)
• OB: Use during pregnancy only if potential maternal benefit justifies potential fetal risk
• Lactation: Safety not established in breastfeeding
• Pedi: Safety and effectiveness not established in children ≤3 yr (PO) or <1 mo (parenteral).

CV: QT interval prolongation, myocardial ischemia, TORSADES DE POINTES.

Derm: STEVENS-JOHNSON SYNDROME, TOXIC EPIDERMAL NECROLYSIS.

GI: constipation, diarrhea, ↑ liver enzymes, abdominal pain, dry mouth.

Neuro: headache, dizziness, drowsiness, extrapyramidal reactions, fatigue, SEROTONIN SYNDROME, weakness.

Drug-Drug:

• Use with apomorphine ↑ risk of severe hypotension and loss of consciousness; concurrent use contraindicated.
• Carbamazepine, phenytoin, and rifampin may ↓ levels.
• Drugs that affect serotonergic neurotransmitter systems, including SSRIs, SNRIs, tricyclic antidepressants, MAOIs, fentanyl, lithium, buspirone, tramadol, methylene blue, and triptans, ↑ risk of serotonin syndrome.

(Generic available)

• Tablets: 4 mg; 8 mg; 24 mg;
• Orally disintegrating tablets (contain aspartame) (strawberry flavor): 4 mg; 8 mg;
• Oral solution (strawberry flavor): 4 mg/5 mL;
• Solution for injection: 2 mg/mL;

Prevention of Nausea/Vomiting Associated With Highly or Moderately Emetogenic Chemotherapy

• PO (Adults): Highly-emetogenic chemotherapy: 24 mg 30 min prior to chemotherapy.
• PO (Adults and Children >11 yr): Moderately emetogenic chemotherapy: 8 mg 30 min prior to chemotherapy and repeated 8 hr later; 8 mg every 12 hr may be given for 1–2 days following chemotherapy.
• PO (Children 4–11 yr): Moderately emetogenic chemotherapy: 4 mg 30 min prior to chemotherapy and repeated 4 and 8 hr later; 4 mg every 8 hr may be given for 1–2 days following chemotherapy.
• IV (Adults): 0.15 mg/kg (max dose = 16 mg) 30 min prior to chemotherapy, repeated 4 and 8 hr later.
• IV (Children 6 mo–18 yr): 0.15 mg/kg (max dose = 16 mg) 30 min prior to chemotherapy, repeated 4 and 8 hr later.

Prevention of Postoperative Nausea/Vomiting

• PO (Adults): 16 mg 1 hr before induction of anesthesia.
• IM, IV (Adults and Children >12 yr): 4 mg before induction of anesthesia or postoperatively.
• IV (Children 1 mo–12 yr and >40 kg): 4 mg before induction of anesthesia or postoperatively.
• IV (Children 1 mo–12 yr and ≤40 kg): 0.1 mg/kg before induction of anesthesia or postoperatively.

Prevention of Nausea/Vomiting Associated With Radiation Therapy

• PO (Adults): 8 mg 1–2 hr prior to radiation; may be repeated every 8 hr, depending on type, location, and extent of radiation.

Zuplenz

• Blocks the effects of serotonin at 5-HT₃ receptor sites (selective antagonist) located in vagal nerve terminals and the chemoreceptor trigger zone in the CNS.

• Decreased incidence and severity of nausea and vomiting following chemotherapy, radiation, or surgery.

Therapeutic Classification: antiemetics

Pharmacologic Classification: five ht3 antagonists

Absorption: IV administration results in complete bioavailability; 100% absorbed following oral administration.

Distribution: Unknown.

Metabolism/Excretion: Extensively metabolized by the liver (primarily by CYP3A4); 5% excreted unchanged by the kidneys.

Half-life: Adults: 3.5–5.5 hr; Children 5 mo–12 yr: 2.9 hr.

Ondissolve ODF, Zofran, Zofran ODT

(antiemetic effect)

• Instruct patient to take ondansetron as directed.
• Advise patient to notify health care professional immediately if symptoms of irregular heartbeat, serotonin syndrome, or involuntary movement of eyes, face, or limbs occur.
• Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

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