NATIONAL
CALIFORNIA
VENTURA
mechanism
- Ondansetron is a selective 5-HT3-receptor antagonist which blocks serotonin, both peripherally on vagal nerve terminals and centrally in the chemoreceptor trigger zone
indications
- Treatment of nausea/vomiting
- Prevention of nausea/vomiting when administering opiates
contraindications
- Allergy to ondansetron or another 5-HT3 receptor antagonist (drugs ending in -setron)
dosing
Adult
Oral, IV, IM: 4 mg
Pediatric
IV, IM: 0.15 mg/kg
Oral:
8 to 15 kg: 2 mg
>15 kg: 4 mg
>15 kg: 4 mg
administration
For oral dissolving tablet, do not remove from blister until needed. Peel backing off the blister, do not attempt to push tablet through the foil. Using dry hands, place tablet on tongue and allow to dissolve. Swallow with saliva (no need to administer with liquids).
IV doses should be administered over 30 seconds to minimize adverse reactions.
onset
30 minutes
peak
2 hours
duration
4-8 hours
notes
- Serotonin syndrome: Serotonin syndrome has been reported with 5-HT3 receptor antagonists, predominantly when used in combination with other serotonergic agents (eg, selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, monoamine oxidase inhibitors, mirtazapine, fentanyl, lithium, tramadol, and/or methylene blue).
dosage form
Injection Solution: 4 mg/2 mL (2 mL)
Oral Disintegrating Tablet: 4 mg
brand name
Zofran
adverse reactions
- Cardiac
- Prolonged QT interval
- Bradycardia
- Torsades de pointes
- Central Nervous System
- Headache
- Dizziness
- Drowsiness
- Weakness
- Gastrointestinal
- Constipation
- Diarrhea
- Abdominal pain
- Dry mouth
structure
