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.
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.
Hepatic Impairment
- PO IM IV (Adults ): Severe hepatic impairment: Not to exceed 8 mg/day.
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.
Hepatic Impairment
- PO IM IV (Adults ): Severe hepatic impairment: Not to exceed 8 mg/day.
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.
Hepatic Impairment
- PO IM IV (Adults ): Severe hepatic impairment: Not to exceed 8 mg/day.
