Ondansetron Injection (Ondansetron Hydrochloride Monohydrate)

Adult dosage

1. Nausea and vomiting induced by cytotoxic chemotherapy or radiation therapy 1) Adults The emetogenic potential of cancer treatment varies depending on the dose of the chemotherapeutic agent, concomitant medications, and type of radiation therapy. The route and dose may be selected as appropriate within a range of 8∼32mg of ondansetron per day, administered orally, intravenously, or intramuscularly. (1) For relatively mildly emetogenic chemotherapy and radiation therapy ① Immediately before chemotherapy or radiation therapy, administer 8mg of ondansetron by slow intravenous injection (over at least 30 seconds) or intramuscular injection, or administer 8mg orally 1∼2 hours before treatment and 8mg orally 12 hours later. ② To prevent delayed vomiting, administer 8mg orally twice daily for up to 5 days after treatment. (2) For administration of highly emetogenic chemotherapeutic agents (e.g., high-dose cisplatin) ① Immediately before chemotherapy, administer 8mg of ondansetron by slow intravenous injection (over at least 30 seconds) or intramuscular injection, followed by 2 additional intravenous injections (over at least 30 seconds) or intramuscular injections of 8mg at 4-hour intervals, or administer by continuous intravenous infusion at a rate of 1mg per hour for up to 24 hours. ② Alternatively, dilute 16mg of ondansetron in 50∼100mL of normal saline or another compatible injection solution and administer by intravenous infusion over at least 15 minutes immediately before chemotherapy. ③ Because the risk of QT prolongation increases in a dose-dependent manner, do not exceed a single dose of 16mg (injection only). ④ The effect of this drug may be enhanced by slow intravenous injection of 20mg of dexamethasone sodium phosphate before chemotherapy (injection only). ⑤ Oral dexamethasone sodium phosphate 12mg and a single oral dose of up to 24mg of ondansetron may be administered together 1~2 hours before chemotherapy (oral formulation only). ⑥ To prevent delayed vomiting, administer 8mg orally twice daily for up to 5 days after treatment. 3) Elderly patients ⦁Oral administration: Follow the recommended adult dose. ⦁Intravenous administration: For patients aged 65 to 74 years, follow the recommended adult dose. For intravenous administration, all doses must be diluted in 50∼100mL of normal saline or another compatible injection solution and infused over at least 15 minutes. For patients aged 75 years and older, the initial intravenous dose must not exceed 8mg. For intravenous administration, all doses must be diluted in 50∼100mL of normal saline or another compatible injection solution and infused over at least 15 minutes. 4) Patients with renal impairment No special dosage adjustment is required. 5) Patients with hepatic impairment In patients with moderate to severe hepatic impairment, the clearance of this drug is substantially reduced and its serum half-life is markedly prolonged; therefore, do not exceed 8mg per day. 2. Postoperative nausea and vomiting 1) Adults (1) Prevention of postoperative nausea and vomiting ① Administer 16mg orally as a single dose 1 hour before induction of anesthesia. ② Administer 4mg by slow intravenous or intramuscular injection at induction of anesthesia. (2) Treatment of postoperative nausea and vomiting Administer 4mg by slow intravenous or intramuscular injection as a single dose. 3) Elderly patients Experience with use in patients aged 65 years and older is limited; however, tolerability was good in patients who received chemotherapy. 4) Patients with renal impairment No special dosage adjustment is required. 5) Patients with hepatic impairment In patients with moderate to severe hepatic impairment, the clearance of this drug is substantially reduced and its serum half-life is markedly prolonged; therefore, do not exceed 8mg per day. 6) Patients with impaired sparteine/debrisoquine metabolism The elimination half-life of this drug is unchanged in patients with impaired sparteine/debrisoquine metabolism. Repeated administration of this drug in such patients does not result in differences in drug exposure compared with the general population; therefore, no adjustment of the daily dose, frequency of administration, or route of administration is required.

Children's dosage

1. Nausea and vomiting induced by cytotoxic chemotherapy or radiotherapy 2) Pediatric patients (6 months and older) Ondansetron hydrochloride (hydrate) injection should be diluted with 5% dextrose injection, 0.9% sodium chloride injection, or another compatible injection solution and administered by intravenous infusion over at least 15 minutes. In pediatric clinical trials, ondansetron was diluted in 25~50mL of normal saline injection or another compatible injection solution and administered by intravenous infusion over at least 15 minutes. (1) Immediately before chemotherapy, administer ondansetron 5mg/㎡ (body surface area) by intravenous injection. Administer the oral dose 12 hours after the intravenous injection; treatment may continue for up to 5 days. Body surface area < 0.6 ㎡: On day 1, administer 5mg/㎡ by intravenous injection, followed by 2mg orally 12 hours later; on days 2~6, administer 2mg orally every 12 hours. Do not exceed 8mg by intravenous injection. The total daily dose should not exceed the adult dose of 32mg. Body surface area ≥ 0.6 ㎡ and ≤ 1.2㎡: On day 1, administer 5mg/㎡ by intravenous injection, followed by 4mg orally 12 hours later; on days 2~6, administer 4mg orally every 12 hours. Do not exceed 8mg by intravenous injection. The total daily dose should not exceed the adult dose of 32mg. Body surface area > 1.2㎡: On day 1, administer 5mg/㎡ or 8mg by intravenous injection, followed by 8mg orally 12 hours later; on days 2~6, administer 8mg orally every 12 hours. Do not exceed 8mg by intravenous injection. The total daily dose should not exceed the adult dose of 32mg. (2) Alternatively, immediately before chemotherapy, administer ondansetron 0.15 mg/kg by intravenous injection. Two additional intravenous injections may be given at 4-hour intervals. Administer the oral dose 12 hours after the intravenous injection; treatment may continue for up to 5 days. Body weight ≤ 10 kg: On day 1, administer 0.15 mg/kg per dose by intravenous injection every 4 hours, up to a maximum of 3 doses; on days 2~6, administer 2mg orally every 12 hours. Do not exceed 8mg by intravenous injection. The total daily dose should not exceed the adult dose of 32mg. Body weight > 10 kg: On day 1, administer 0.15 mg/kg per dose by intravenous injection every 4 hours, up to a maximum of 3 doses; on days 2~6, administer 4mg orally every 12 hours. Do not exceed 8mg by intravenous injection. The total daily dose should not exceed the adult dose of 32mg. (3) Do not exceed 8mg by intravenous injection. The total daily dose should not exceed the adult dose of 32mg. (4) There are no controlled clinical trial data on the prevention of delayed or persistent nausea and vomiting caused by emetogenic chemotherapy. There are no controlled pediatric clinical trial data on nausea and vomiting caused by radiotherapy. 2. Postoperative nausea and vomiting 2) Pediatric patients (2 years and older) (1) Prevention of postoperative nausea and vomiting Before, during, or after induction of anesthesia, administer a single dose of 0.1mg/kg, up to a maximum of 4mg, by slow intravenous injection. (2) Treatment of postoperative nausea and vomiting Administer a single dose of 0.1mg/kg, up to a maximum of 4mg, by slow intravenous injection. (3) Data are insufficient for the prevention and treatment of postoperative nausea and vomiting in children younger than 2 years. (4) As no clinical trials have been conducted on the use of oral ondansetron for the prevention and treatment of postoperative nausea and vomiting, slow intravenous injection (over 30 seconds or longer) is recommended.

This medication may allow glass fragments to enter when using glass ampules; therefore, extreme caution is required, especially when administering to children or the elderly. Patients with allergies to this drug's components or those using it in conjunction with the specific medication apomorphine may experience severe hypotension and loss of consciousness, so co-administration should be avoided. Patients who have shown allergic reactions to similar medications in the past should be careful, as they may exhibit allergic reactions to this drug as well. This medication may slow intestinal motility, so patients with signs of intestinal obstruction must be closely monitored after administration. Use this drug cautiously in patients with severely impaired liver function, those with cardiac electrical activity anomalies, and patients with electrolyte imbalances. Particularly, this medication can prolong the QT interval, so patients with heart disease or at risk of QT interval prolongation should be cautious. When combined with other serotonergic drugs, there is a risk of serious side effects known as serotonin syndrome, so patients must be closely monitored. This medication, when used post-surgery for nausea and vomiting prevention, may mask the risk of bleeding, so careful observation is required after administration. In pediatric patients, the risk of liver damage exists, so liver function must be monitored closely. If any allergic reactions occur, such as rash, itching, or difficulty breathing while taking this medication, administration must be stopped immediately, and appropriate treatment should be sought. Neurological side effects such as headache, dizziness, drowsiness, or muscle tone abnormalities may occur rarely, so any unusual symptoms should be reported. Gastrointestinal symptoms such as diarrhea or constipation may occur, which requires monitoring. Cardiac irregularities, blood pressure changes, and, rarely, significant arrhythmias may occur, so cardiac status must be monitored. Liver function tests may show a temporary increase, necessitating checks on liver health. Rarely, temporary vision disturbances or vision loss may occur, so any visual changes experienced should be discussed with a healthcare professional. Very rarely, serious skin reactions may be observed, so skin condition should be monitored closely. This medication is unlikely to impair driving or machine operation ability; however, caution is needed as it may vary from person to person. In cases of overdose, visual disturbances, severe constipation, blood pressure drops, and cardiac electrical anomalies may occur, requiring immediate medical attention. This medication needs to be used with caution when mixed with other drugs, and any remaining medication after use should be discarded. When storing, keep it in an airtight sealed container, away from direct sunlight, and out of reach of children, and avoid transferring it to other containers.

Rash, itching, anaphylaxis, headache, heaviness, drowsiness, flushing, warmth in the head and abdomen, increased aminotransferases, dizziness, ocular myoclonus, muscle rigidity abnormal reactions, dyskinesia, seizures, diarrhea, constipation, palpitations, increased blood pressure, chest pain, arrhythmia, hypotension, bradycardia, QTc prolongation, elevated liver function tests, visual disturbances, vision loss, toxic skin rash, involuntary movements, warmth, generalized malaise, hiccups, sweating, vascular pain, local hypersensitivity reaction at the injection site

This medication should be stored in a sealed container to prevent air ingress, away from direct sunlight, and in a cool place below 30 degrees Celsius. Proper storage conditions will help maintain the drug's effectiveness for a longer period.

Appearance

A colorless and transparent solution in a colorless and transparent ampule.

Package unit

10 ampules/box [4mg/2mL/ampule X10], 10 ampules/box [8mg/4mL/ampule X10]