Ondansetron Dosage

Usual Adult Dose for Nausea/Vomiting - Chemotherapy Induced

Initial: 0.15 mg/kg IV given 30 minutes before the start of emetogenic therapy, then repeat the dose at 4 hour intervals for 2 additional doses. A continuous IV dose option consists of 8 mg followed by 1 mg/hr for the next 24 hours.

Alternative therapies:
With highly emetogenic chemotherapy, give a onetime IV dose of 32 mg, 30 minutes before the start of single-day therapy; Infuse over 15 minutes. Alternatively, give a single 24 mg orally 30 minutes before therapy.
With moderate emetogenic chemotherapy, give 8 mg orally 30 minutes before the start of therapy, then 8 mg given 8 hours after the first dose. Thereafter, give 8 mg every 12 hours for 1 to 2 days after emetogenic therapy is complete.

Oral soluble film dosage form: Highly emetogenic cancer chemotherapy: 24 mg given successively as three 8 mg films administered 30 minutes before the start of single-day highly emetogenic chemotherapy, including cisplatin greater than or equal to 50 mg/m2. Moderately emetogenic cancer chemotherapy: One 8 mg soluble film given 2 times a day. The first dose should be administered 30 minutes before the start of emetogenic chemotherapy, with a subsequent dose 8 hours after the first dose.

Usual Adult Dose for Nausea/Vomiting

Initial: 0.15 mg/kg IV given 30 minutes before the start of emetogenic therapy, then repeat the dose at 4 hour intervals for 2 additional doses. A continuous IV dose option consists of 8 mg followed by 1 mg/hr for the next 24 hours.

Alternative therapies:
With highly emetogenic chemotherapy, give a onetime IV dose of 32 mg, 30 minutes before the start of single-day therapy; Infuse over 15 minutes. Alternatively, give a single 24 mg orally 30 minutes before therapy.
With moderate emetogenic chemotherapy, give 8 mg orally 30 minutes before the start of therapy, then 8 mg given 8 hours after the first dose. Thereafter, give 8 mg every 12 hours for 1 to 2 days after emetogenic therapy is complete.

Oral soluble film dosage form: Highly emetogenic cancer chemotherapy: 24 mg given successively as three 8 mg films administered 30 minutes before the start of single-day highly emetogenic chemotherapy, including cisplatin greater than or equal to 50 mg/m2. Moderately emetogenic cancer chemotherapy: One 8 mg soluble film given 2 times a day. The first dose should be administered 30 minutes before the start of emetogenic chemotherapy, with a subsequent dose 8 hours after the first dose.

Usual Adult Dose for Nausea/Vomiting - Postoperative

4 mg IV (undiluted) over 2 to 5 minutes, or IM, immediately before induction of anesthesia or postoperatively if nausea or vomiting occurs immediately after surgery. Alternatively, 16 mg orally 1 hour before induction of anesthesia.

Oral soluble film dosage form: 16 mg given as successively as two 8 mg oral soluble films 1 hour before induction of anesthesia.

Usual Adult Dose for Nausea/Vomiting-Radiation Induced

8 mg orally every 8 hours, give the first dose 1 to 2 hours prior to radiotherapy.

Oral soluble film dosage form:
One 8 mg soluble film given 3 times a day.
For total body irradiation: One 8 mg soluble film given 1 to 2 hours before each fraction of radiotherapy administered each day.
For single high-dose fraction radiotherapy to the abdomen: One 8 mg oral soluble film given 1 to 2 hours before radiotherapy, with subsequent doses every 8 hours after the first dose for 1 to 2 days after completion of radiotherapy.
For daily fractionated radiotherapy to the abdomen: One 8 mg oral soluble film given 1 to 2 hours before radiotherapy, with subsequent doses every 8 hours after the first dose for each day radiotherapy is given.

Usual Adult Dose for Pruritus

Study (n=150) - Induced by Intrathecal Fentanyl
8 mg IV before spinal anesthesia.

Usual Adult Dose for Alcohol Dependence

Study (n=321) - Early onset alcoholism
4 mcg/kg two times daily.

Usual Adult Dose for Postanesthetic Shivering

Study (n=82)
8 mg IV, 3 to 5 minutes before the induction of anesthesia.

Usual Pediatric Dose for Nausea/Vomiting - Postoperative

Child 1 month to 12 years:
40 kg or less: 0.1 mg/kg single dose IV, administered over 2 to 5 minutes, immediately prior to or following anesthesia induction, or postoperatively if nausea and/or vomiting present shortly after surgery.

40 kg or more: 4 mg single dose IV, administered over 2 to 5 minutes, immediately prior to or following anesthesia induction, or postoperatively if nausea and/or vomiting present shortly after surgery.

Usual Pediatric Dose for Nausea/Vomiting - Chemotherapy Induced

Child 6 months to 18 years: 0.15 mg/kg as an IV infusion (over 15 minutes) administered 30 minutes before the start of emetogenic therapy, then at 4 and 8 hours after the first dose, respectively.

4 to 11 years: 4 mg orally given 30 minutes before the start of emetogenic therapy, then 4 mg orally 4 and 8 hours after the first dose. Thereafter, 4 mg orally every 8 hours for 1 to 2 days after emetogenic therapy is complete.

11 years or older:: 8 mg orally 3 times daily, or 24 mg orally once daily.

Oral soluble film dosage form: Use of ondansetron oral soluble films is not indicated for treatment of nausea and vomiting associated with highly emetogenic cancer chemotherapy in pediatric patients.
For prevention of nausea and vomiting associated with moderately emetogenic cancer chemotherapy: For pediatric patients 12 years of age and older, the dosage is the same as for adults. For pediatric patients 4 through 11 years of age, the dosage is one 4 mg oral soluble film given 3 times a day. The first dose should be administered 30 minutes before the start of emetogenic chemotherapy, with subsequent doses 4 and 8 hours after the first dose. One 4 mg oral soluble film should be administered 3 times a day (every 8 hours) for 1 to 2 days after completion of chemotherapy.

Usual Pediatric Dose for Gastroenteritis

Study (n=145) - Control of emesis during the ED phase of oral rehydration:
6 months to 12 months: 1.6 mg orally every 8 hours
1 year to 3 years: 3.2 mg orally every 8 hours
4 years or older: 4 mg orally every 8 hours

Dosage was administered 15 minutes before the start of oral rehydration.

Renal Dose Adjustments

No adjustments recommended

Liver Dose Adjustments

A total daily dose of 8 mg should not be exceeded in patients with severe hepatic impairment (Child-Pugh score of 10 or greater). Infuse the 8 mg IV dose over 15 minutes, 30 minutes before the start of emetogenic chemotherapy.

Oral soluble film dosage form: In patients with severe hepatic impairment (Child-Pugh score of 10 or greater), clearance is reduced and apparent volume of distribution is increased with a resultant increase in plasma half-life. In such patients, a total daily dose of 8 mg should not be exceeded.

Precautions

The manufacturer recommends that pediatric patients 1 month to 4 months of age who are receiving this drug be closely monitored because the clearance in this age group is slower and the half-life is longer (approximately 2.5-fold longer) than in patients who are 4 to 24 months of age.

Patients diagnosed with phenylketonuria should be informed that ondansetron orally disintegrating tablets (Zofran ODT) contain phenylalanine (less than 0.03 mg).

The concurrent administration of apomorphine with ondansetron is contraindicated based on reports of profound hypotension and loss of consciousness.

Safety and effectiveness of ondansetron oral soluble films for highly emetogenic cancer chemotherapy, prevention of nausea and vomiting associated with radiotherapy, and prevention of postoperative nausea and vomiting have not been established in pediatric patients (less than 18 years of age).

Dialysis

Data not available

Other Comments

All injectable preparation should be inspected visually for discoloration and particulate matter.

All infusions should be given over 15 minutes. The necessity of continuing ondansetron therapy should be assessed frequently.

The injectable preparation is intended for IV or IM use only. Give the IV dose undiluted over 2 to 5 minutes (never faster than 30 seconds).

The manufacturer recommends shaking the vial if a precipitate is observed; potency and safety are not affected. The precipitate is occasionally found at the stopper/vial interface in vials stored upright.

Ondansetron oral soluble films should be placed on the top of the tongue, where it will dissolve in 4 to 20 seconds. Each film should be allowed to dissolve completely before administering the next film. Once the oral soluble film is dissolved, it may be swallowed with or without liquid.

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