CHEMOTHERAPY AND RADIOTHERAPY INDUCED NAUSEA AND VOMITING (CINV and RINV)
Adults
The emetogenic potential of cancer treatment varies according to the doses and combinations of chemotherapy and radiotherapy regimens used. The selection of dose regimen should be determined by the severity of the emetogenic challenge.
Emetogenic chemotherapy and radiotherapy:
The recommended oral dose is 8 mg (5 ml) 1-2 hours before treatment, followed by 8 mg (5 ml) orally every 12 hours for a maximum of 5 days to protect against delayed or prolonged emesis.
Highly emetogenic chemotherapy:
For patients receiving highly emetogenic chemotherapy a single oral dose of up to 24 mg (15 ml) ondansetron taken together with 12 mg oral dexamethasone sodium phosphate, 1 to 2 hours before chemotherapy, may be used.
To protect against delayed or prolonged emesis after the first 24 hours, oral or rectal treatment with ondansetron may be continued for up to 5 days after a course of treatment.
The recommended oral dose is 8 mg (5 ml) to be taken twice daily.
Paediatric Population
CINV in children and adolescents aged 6 months to 17 years
The dose of CINV can be calculated based on body surface area (BSA) or weight. Weight-based dosing results in higher total daily doses compared to BSA-based dosing (section 4.4 and 5.1). In paediatric clinical studies, ondansetron was given by IV infusion diluted in 25 to 50 mL of saline or other compatible infusion fluid and infused over not less than 15 minutes. Weight-based dosing results in higher total daily doses compared to BSA-based dosing (see section 4.4).
There are no data from controlled clinical trials on the use of ondansetron in the prevention of delayed or prolonged CINV. There are no data from controlled clinical trials on the use of ondansetron for radiotherapy-induced nausea and vomiting in children.
Dosing by Body Surface Area (BSA)
Ondansetron should be administered immediately before chemotherapy as a single IV dose of 5 mg/m2.
The single IV dose must not exceed 8 mg. Oral dosing can commence twelve hours later and may be continued for up to 5 days (Table 1).
The total dose over 24 hours (given as divided doses) must not exceed adult dose of 32 mg.
Table 1. BSA-based dosing for CINV (aged 6 months to 17 years)
| BSA | Day 1 (a, b) | Days 2-6 (b) |
| < 0.6 m2 | 5 mg/m2 IV plus 2 mg syrup (equivalent to 1.25 ml of syrup) after 12 hours | 2 mg syrup (equivalent to 1.25 ml of syrup) every 12 hours |
| > 0.6 m2 to ≤ 1.2 m2 | 5 mg/m2 IV plus 4 mg syrup (equivalent to 2.5 ml of syrup) or one 4 mg tablet after 12 hours | 4 mg syrup (equivalent to 2.5 ml of syrup) or one 4 mg tablet every 12 hours |
| > 1.2 m2 | 5 mg/m2 or 8 mg IV plus 8 mg syrup (equivalent to 5 ml of syrup) or tablet after 12 hours | 8 mg syrup (equivalent to 5 ml of syrup) or tablet every 12 hours |
a The intravenous dose must not exceed 8 mg
b the total dose over 24 hours (given as divided doses) must not exceed adult dose of 32 mg
Dosing by bodyweight
Weight-based dosing results in higher total daily doses compared to BSA-based dosing (section 4.4 and 5.1).
Ondansetron should be administered immediately before chemotherapy as a single IV dose of 0.15 mg/kg. The single IV dose must not exceed 8 mg.
Two further IV doses may be given in 4-hourly intervals.
Oral dosing can commence twelve hours later and may be continued for up to 5 days (Table 2).
The total dose over 24 hours (given as divided doses) must not exceed adult dose of 32 mg.
Table 2. Weight-based dosing for CINV (aged 6 months to 17 years)
| Body Weight | Day 1 (a, b) | Days 2-6 (b) |
| ≤ 10 kg | Up to 3 doses of 0.15 mg/kg IV every 4 hours | 2 mg syrup (equivalent to 1.25 ml of syrup) every 12 hours |
| > 10 kg | Up to 3 doses of 0.15 mg/kg IV every 4 hours | 4 mg syrup (equivalent to 2.5 ml of syrup) or tablet every 12 hours |
a The intravenous dose must not exceed 8 mg
b the total dose over 24 hours (given as divided doses) must not exceed adult dose of 32 mg.
Elderly:
No alteration of oral dose or frequency of administration is required.
POST OPERATIVE NAUSEA AND VOMITING (PONV)
Adults
For prevention of post-operative nausea and vomiting the recommended oral dose is16 mg (10 ml) given one hour prior to anaesthesia.
For treatment of established post-operative nausea and vomiting, intravenous or intramuscular administration is recommended.
Paediatric population
PONV in children and adolescents (aged 1 month to 17 years)
Oral formulation:
No studies have been conducted on the use of orally administered ondansetron in the prevention or treatment of post-operative nausea and vomiting; slow IV injection (not less than 30 seconds) is recommended for this purpose.
Injection:
For prevention of PONV in paediatric patients having surgery performed under general anaesthesia, a single dose of ondansetron may be administered by slow intravenous injection (not less than 30 seconds) at a dose of 0.1 mg/kg up to a maximum of 4 mg (i.e. 2.5 ml) either prior to, at or after induction of anaesthesia.
For the treatment of PONV after surgery in paediatric patients having surgery performed under general anaesthesia, a single dose of Ondansetron may be administered by slow intravenous injection (not less than 30 seconds) at a dose of 0.1 mg/kg up to a maximum of 4 mg (i.e. 2.5 ml).
There are no data on the use of ondansetron in the treatment of PONV in children under 2 years of age.
Elderly
There is limited experience in the use of ondansetron in the prevention and treatment of PONV in the elderly, however ondansetron is well tolerated in patients over 65 years receiving chemotherapy.
PATIENTS WITH RENAL/HEPATIC IMPAIRMENT:
Patients with Renal Impairment:
No alteration of daily dosage or frequency of dosing, or route of administration are required.
Patients with Hepatic Impairment:
Clearance of ondansetron is significantly reduced and serum half-life significantly prolonged in subjects with moderate or severe impairment of hepatic function. In such patients, a total daily dose of 8 mg (5 ml) oral should not be exceeded.
PATIENTS WITH POOR SPARTEINE/DEBRISOQUINE METABOLISIM:
The elimination half-life of ondansetron is not altered in subjects classified as poor metabolisers of sparteine and debrisoquine. Consequently in such patients repeat dosing will give drug exposure levels no different from those of the general population. No alteration of daily dosage or frequency of dosing is required.
Method of administration
For oral administration only.