Page 159 - 2026 SMOG

ONDANSETRON (ZOFRAN)
Class/Mechanism of Action
• Antiemetic
Blocks serotonin peripherally on vagus nerve terminals and centrally.
˚ Onset of action: 5–30min dependent on route
Indications
• Labeled Indications
˚ Prevention of postoperative nausea and vomiting
• Off-Label Indications
˚ Hyperemesis gravidarum (severe or refractory)
Contraindications
• Hypersensitivity to ondansetron or any component of the formulation
Adverse Reactions/Precautions
• Dose-dependent QT interval prolongation occurs, and IV doses >16mg are not recommended.
In most patients, QT changes are not clinically relevant; however, if used with other
medications that prolong QT intervals (antiarrhythmics) or in those at risk for QT prolongation,
arrhythmia can occur. Torsades de points have been reported.
• Pregnancy: Category B
• Lactation: Use caution
Dose/Administration
PEDIATRIC
ADULT
(Always reference Broselow Tape)
Nausea and Vomiting Nausea and Vomiting (Children 1 Month to
• IV/IO/IM/PO/ODT 12 Years)
˚ 4–8mg • IV
Treatment of Severe or Refractory ˚ 0.15–0.3mg/kg (max SINGLE dose: 8mg)
Hyperemesis Gravidum (Off-Label use)
• IV
˚ 8mg administered over 15min q12hr

2026 Standard Medical Operating Guidelines (SMOG) • 151