How is ondansetron used to prevent nausea and vomiting. What are the recommended dosages for adults and children. How should ondansetron be administered for chemotherapy-induced nausea. What precautions should be taken when using ondansetron.

Understanding Ondansetron: A Powerful Antiemetic Medication

Ondansetron is a widely prescribed antiemetic medication used to prevent and treat nausea and vomiting associated with various medical conditions and treatments. This article provides a comprehensive overview of ondansetron, including its uses, dosages, and administration guidelines for both adults and children.

Ondansetron for Chemotherapy-Induced Nausea and Vomiting

One of the primary uses of ondansetron is preventing nausea and vomiting caused by chemotherapy. The dosage and administration method depend on the emetogenic potential of the chemotherapy regimen.

Highly Emetogenic Chemotherapy (HEC)

For adults undergoing highly emetogenic chemotherapy, such as cisplatin doses of 50 mg/m2 or greater, the recommended oral dose is 24 mg taken 30 minutes before the start of single-day HEC. It’s important to note that multi-day, single-dose administration of 24 mg orally for HEC has not been studied extensively.

Moderately Emetogenic Chemotherapy (MEC)

Adults receiving moderately emetogenic chemotherapy should take 8 mg orally twice a day. The first dose should be administered 30 minutes before the start of chemotherapy, with a subsequent dose 8 hours later. This regimen is followed by 8 mg orally twice daily (every 12 hours) for 1 to 2 days after completing chemotherapy.

Intravenous Administration for Chemotherapy-Induced Nausea

For intravenous administration, the recommended dose is 0.15 mg/kg. The first dose should be infused over 15 minutes, 30 minutes before the start of emetogenic chemotherapy. Subsequent doses are given 4 and 8 hours after the first dose. The maximum dose per administration is 16 mg.

Ondansetron for Postoperative Nausea and Vomiting

Ondansetron is also effective in preventing postoperative nausea and vomiting. The dosage and administration method differ for oral and parenteral routes.

Oral Administration for Adults

For adults, the recommended oral dose is 16 mg taken 1 hour before the induction of anesthesia.

Parenteral Administration for Adults

When administered parenterally, adults should receive 4 mg intravenously (undiluted) immediately before induction of anesthesia or postoperatively if nausea and/or vomiting occur within 2 hours after surgery. An alternative route is 4 mg intramuscularly (undiluted).

Is a second dose of ondansetron beneficial for postoperative nausea? Studies have shown that administering a second dose does not provide additional control of nausea and vomiting in this context.

Pediatric Dosing for Postoperative Nausea

For children aged 1 month to 12 years, the dosage is weight-based:

• Less than 40 kg: 0.1 mg/kg IV over 2 to 5 minutes
• 40 kg and greater: 4 mg IV over 2 to 5 minutes

This dose should be administered immediately prior to or following anesthesia induction, or postoperatively if nausea and/or vomiting occur shortly after surgery.

Ondansetron for Radiation-Induced Nausea and Vomiting

Ondansetron is also effective in preventing nausea and vomiting associated with radiotherapy. The dosage and administration schedule vary depending on the type of radiation treatment.

Total Body Irradiation

For patients undergoing total body irradiation, the recommended dose is 8 mg orally taken 1 to 2 hours before each fraction of radiotherapy administered each day.

Single High-dose Fraction Radiotherapy to the Abdomen

When receiving a single high-dose fraction of radiotherapy to the abdomen, patients should take 8 mg orally 1 to 2 hours before radiotherapy. Subsequent doses of 8 mg should be taken every 8 hours after the first dose for 1 to 2 days after completing radiotherapy.

Daily Fractionated Radiotherapy to the Abdomen

For daily fractionated radiotherapy to the abdomen, the recommended dose is 8 mg orally taken 1 to 2 hours before radiotherapy. Subsequent doses of 8 mg should be taken every 8 hours after the first dose for each day radiotherapy is given.

Pediatric Dosing for Chemotherapy-Induced Nausea and Vomiting

Ondansetron is also used to prevent chemotherapy-induced nausea and vomiting in children. The dosage varies based on the child’s age and weight.

Oral Administration for Children

For children aged 4 to 11 years, the recommended oral dose is 4 mg taken three times a day. The first dose should be administered 30 minutes before the start of chemotherapy, with subsequent doses given 4 and 8 hours after the first dose. This is followed by 4 mg orally three times daily for up to 5 days after a course of chemotherapy.

Special Considerations and Precautions

While ondansetron is generally well-tolerated, there are several important considerations and precautions to keep in mind when using this medication.

Renal and Hepatic Impairment

Do patients with kidney or liver problems require dose adjustments? In general, no dosage adjustment is necessary for patients with renal or hepatic impairment. However, for patients with severe hepatic impairment, the total daily dose should not exceed 8 mg.

Drug Interactions

Ondansetron can interact with several medications, potentially altering its effectiveness or increasing the risk of side effects. Some important drug interactions to be aware of include:

• Apomorphine: Concurrent use may cause severe hypotension and loss of consciousness
• CYP3A4 inducers (e.g., rifampicin): May decrease ondansetron plasma concentrations
• QT-prolonging drugs: Concurrent use may increase the risk of QT interval prolongation

Pregnancy and Breastfeeding

Is ondansetron safe during pregnancy and breastfeeding? The safety of ondansetron during pregnancy has not been conclusively established. While some studies suggest it may be safe, others have raised concerns about potential risks. It should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus. Ondansetron is excreted in human milk, and caution should be exercised when administering it to nursing women.

Potential Side Effects and Monitoring

While ondansetron is generally well-tolerated, it can cause side effects in some patients. Healthcare providers should monitor patients for potential adverse reactions.

Common Side Effects

The most frequently reported side effects of ondansetron include:

• Headache
• Constipation
• Dizziness
• Fatigue

Serious Side Effects

Although rare, some serious side effects may occur with ondansetron use. These include:

• QT interval prolongation
• Serotonin syndrome
• Hypersensitivity reactions
• Masking of progressive ileus and/or gastric distension

Healthcare providers should educate patients about these potential side effects and advise them to seek medical attention if they experience any concerning symptoms.

Ondansetron in Clinical Practice: Optimizing Use and Patient Outcomes

Ondansetron has revolutionized the management of nausea and vomiting in various clinical settings. To optimize its use and improve patient outcomes, healthcare providers should consider several factors.

Timing of Administration

The timing of ondansetron administration is crucial for its effectiveness. For chemotherapy-induced nausea and vomiting, the first dose should typically be given 30 minutes before the start of chemotherapy. In the case of postoperative nausea and vomiting, administration immediately before anesthesia induction is recommended.

Combination Therapy

Is ondansetron more effective when combined with other antiemetics? In many cases, particularly for highly emetogenic chemotherapy regimens, ondansetron is used as part of a multi-drug antiemetic regimen. Combining ondansetron with corticosteroids (e.g., dexamethasone) and NK1 receptor antagonists (e.g., aprepitant) can provide superior antiemetic control compared to ondansetron alone.

Patient Factors

Individual patient factors can influence the effectiveness of ondansetron and the risk of side effects. These factors include:

• Age
• Gender
• History of motion sickness or previous chemotherapy-induced nausea and vomiting
• Concomitant medications
• Genetic factors affecting drug metabolism

Healthcare providers should consider these factors when determining the optimal ondansetron regimen for each patient.

Alternative Formulations

Ondansetron is available in various formulations, including oral tablets, orally disintegrating tablets, oral solution, and injectable forms. The choice of formulation should be based on the patient’s ability to swallow, the clinical setting, and the severity of nausea and vomiting.

Future Directions and Research

As our understanding of the mechanisms underlying nausea and vomiting continues to evolve, research into ondansetron and other antiemetics is ongoing. Several areas of investigation hold promise for improving the use of ondansetron in clinical practice.

Pharmacogenomics

How do genetic factors influence ondansetron’s effectiveness and side effect profile? Ongoing research is exploring the role of genetic variations in enzymes involved in ondansetron metabolism, such as CYP2D6. This research may lead to more personalized dosing strategies based on a patient’s genetic profile.

Novel Formulations

Researchers are exploring new formulations of ondansetron that may offer advantages in terms of convenience, absorption, or duration of action. For example, transdermal patches and long-acting injectable formulations are under investigation.

Combination Therapies

Ongoing studies are evaluating novel combinations of ondansetron with other antiemetics or supportive care medications to enhance its efficacy and reduce side effects.

Expanded Indications

While ondansetron is primarily used for chemotherapy-induced, postoperative, and radiation-induced nausea and vomiting, researchers are exploring its potential in other conditions associated with nausea and vomiting, such as cyclic vomiting syndrome and hyperemesis gravidarum.

As research in these areas progresses, it is likely that our approach to using ondansetron will continue to be refined, leading to improved patient outcomes and quality of life.

Ondansetron Dosage Guide + Max Dose, Adjustments

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Medically reviewed by Drugs.com. Last updated on Nov 28, 2022.

Applies to the following strengths: 4 mg/5 mL; 32 mg/50 mL-D5%; 2 mg/mL; 4 mg; 8 mg; 24 mg; 32 mg/50 mL-NaCl 0.9%

Usual Adult Dose for:

• Nausea/Vomiting – Chemotherapy Induced
• Nausea/Vomiting
• Nausea/Vomiting – Postoperative
• Nausea/Vomiting – Radiation Induced

Usual Pediatric Dose for:

• Nausea/Vomiting – Postoperative
• Nausea/Vomiting – Chemotherapy Induced

Additional dosage information:

• Renal Dose Adjustments
• Liver Dose Adjustments
• Precautions
• Dialysis
• Other Comments

Usual Adult Dose for Nausea/Vomiting – Chemotherapy Induced

Oral:
Highly Emetogenic Cancer Chemotherapy (HEC):

• Recommended dose: 24 mg orally 30 minutes before the start of single-day HEC (including cisplatin doses of 50 mg/m2 or greater)

Moderately Emetogenic Cancer Chemotherapy (MEC):

• Recommended dose: 8 mg orally twice a day, with the first dose administered 30 minutes before the start of chemotherapy and the subsequent dose 8 hours later; then 8 mg orally 2 times a day (every 12 hours) for 1 to 2 days after the completion of chemotherapy

Parenteral:

• Recommended dose: 0. 15 mg/kg IV, with the first dose (infused over 15 minutes) 30 minutes before the start of emetogenic chemotherapy and subsequent doses given 4 and 8 hours after the first dose.
• Maximum dose: 16 mg per dose

Comments:

• Multi-day, single-dose administration of 24 mg orally for HEC has not been studied.
• The injection formulation should be diluted prior to IV administration.

Uses:

• Prevention of nausea and vomiting associated with HEC or MEC
• Prevention of nausea and vomiting associated with initial and repeat courses of emetogenic chemotherapy

Usual Adult Dose for Nausea/Vomiting

Oral:
Highly Emetogenic Cancer Chemotherapy (HEC):

• Recommended dose: 24 mg orally 30 minutes before the start of single-day HEC (including cisplatin doses of 50 mg/m2 or greater)

Moderately Emetogenic Cancer Chemotherapy (MEC):

• Recommended dose: 8 mg orally twice a day, with the first dose administered 30 minutes before the start of chemotherapy and the subsequent dose 8 hours later; then 8 mg orally 2 times a day (every 12 hours) for 1 to 2 days after the completion of chemotherapy

Parenteral:

• Recommended dose: 0. 15 mg/kg IV, with the first dose (infused over 15 minutes) 30 minutes before the start of emetogenic chemotherapy and subsequent doses given 4 and 8 hours after the first dose.
• Maximum dose: 16 mg per dose

Comments:

• Multi-day, single-dose administration of 24 mg orally for HEC has not been studied.
• The injection formulation should be diluted prior to IV administration.

Uses:

• Prevention of nausea and vomiting associated with HEC or MEC
• Prevention of nausea and vomiting associated with initial and repeat courses of emetogenic chemotherapy

Usual Adult Dose for Nausea/Vomiting – Postoperative

Oral:

• Recommended dose: 16 mg orally 1 hour before the induction of anesthesia

Parenteral:

• Recommended dose: 4 mg IV (undiluted) immediately before induction of anesthesia or postoperatively (nausea and/or vomiting within 2 hours after surgery)
• Alternative route: 4 mg IM (undiluted)

Comment:

• Administration of a second dose does not provide additional control of nausea and vomiting.

Use:

• Prevention of postoperative nausea and vomiting

Usual Adult Dose for Nausea/Vomiting – Radiation Induced

Recommended dose: 8 mg orally 3 times a day

• Total Body Irradiation: 8 mg orally 1 to 2 hours before each fraction of radiotherapy administered each day
• Single High-dose Fraction Radiotherapy to the Abdomen: 8 mg orally 1 to 2 hours before radiotherapy, with subsequent doses every 8 hours after the first dose for 1 to 2 days after the completion of radiotherapy
• Daily Fractionated Radiotherapy to the Abdomen: 8 mg orally 1 to 2 hours before radiotherapy, with subsequent doses every 8 hours after the first dose for each day radiotherapy is given

Use:

• Prevention of nausea and vomiting associated with radiotherapy, either as total body irradiation, single high-dose fraction, or daily fractions to the abdomen

Usual Pediatric Dose for Nausea/Vomiting – Postoperative

Parenteral:
1 month to 12 years:
Less than 40 kg:

• Recommended dose: 0. 1 mg/kg IV over 2 to 5 minutes immediately prior to/following anesthesia induction or postoperatively (nausea and/or vomiting occurring shortly after surgery)

40 kg and greater:

• Recommended dose: 4 mg IV over 2 to 5 minutes immediately prior to/following anesthesia induction or postoperatively (nausea and/or vomiting occurring shortly after surgery)

Use:

• Prevention of postoperative nausea and vomiting

Usual Pediatric Dose for Nausea/Vomiting – Chemotherapy Induced

Oral:
4 to 11 years:

• Recommended dose: 4 mg orally 3 times a day, with the first dose administered 30 minutes before the start of chemotherapy, and subsequent doses 4 and 8 hours after the first dose; then 4 mg orally 3 times a day (every 8 hours) for 1 to 2 days after the completion of chemotherapy

12 years and older:

• Recommended dose: 8 mg orally twice a day, with the first dose administered 30 minutes before the start of chemotherapy and the subsequent dose 8 hours later; then 8 mg orally 2 times a day (every 12 hours) for 1 to 2 days after the completion of chemotherapy

Parenteral:
6 months to 18 years:

• Recommended dose: 0. 15 mg/kg IV, with the first dose (infused over 15 minutes) 30 minutes before the start of emetogenic chemotherapy, and subsequent doses given 4 and 8 hours after the first dose
• Maximum dose: 16 mg (per dose)

Comments:

• The injection formulation should be diluted in 50 mL prior to IV administration.
• This drug should be used to prevent nausea and vomiting associated with moderately to highly emetogenic chemotherapy.

Uses:

• Prevention of nausea and vomiting associated with moderately emetogenic cancer chemotherapy
• Prevention of nausea and vomiting associated with initial and repeat courses of emetogenic chemotherapy

Renal Dose Adjustments

No adjustment recommended.

Liver Dose Adjustments

• Mild to moderate hepatic impairment (Child-Pugh less than 10): No adjustment recommended.
• Severe hepatic impairment: (Child-Pugh 10 or greater): 8 mg IV over 30 minutes before the start of emetogenic chemotherapy; maximum 8 mg per day

Precautions

Safety and efficacy have not been established in patients younger than 6 months (parenteral formulations) and 4 years (oral formulations).

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• Do not push oral dissolving tablets (ODTs) through the foil backing.
• ODT and film formulations should be used with dry hands and immediately placed on the tongue. The dosage form should dissolve in saliva. Administration with additional liquid is not necessary. In patients requiring multiple films per dose, each film should be allowed to completely dissolve before administering the next film.
• IV doses greater than 8 mg should be slowly injected over at least 15 minutes. Single IV doses greater than 16 mg should be avoided.
• IM doses should be administered undiluted at a rate slower than 30 seconds (e.g., 2 to 5 minutes).
• The suppository formulation is not recommended for use in children.

Storage requirements:

• The manufacturer product information should be consulted.

Reconstitution/preparation techniques:

• The manufacturer product information should be consulted.

IV compatibility:

• The manufacturer product information should be consulted.

General:

• The lowest effective dose should be used.
• Oral, rectal, IV, and IM routes have shown to be equally effective over the first 24 hours of chemotherapy.
• Use of the ODT formulation in the prevention of nausea and vomiting associated with highly-emetogenic chemotherapy, radiotherapy, or in postoperative situations has not been studied in pediatric patients.
• Concomitant use with dexamethasone may potentiate the antiemetic effects of this drug.
• Routine prophylaxis is not recommended for postoperative patients with little expectation of nausea and vomiting; however, use is recommended for patients who should avoid postoperative nausea and vomiting, even with low risk of postoperative nausea and vomiting.

Monitoring:

• Electrolyte levels, especially in patients at risk for hypomagnesemia or hypokalemia
• ECG, especially in patients with a history of QT prolongation, bradycardia, congestive heart failure, or those on drugs which could prolong the QT interval or result in electrolyte abnormalities
• Signs/symptoms of respiratory events or hypersensitivity reactions

Patient advice:

• Inform patients that this drug may cause drowsiness, and they should avoid driving or operating machinery until the full effects of the drug are seen.
• Patients should be advised to immediately report any signs/symptoms associated with serotonin syndrome or hypersensitivity reactions to their prescribers. Patients should also report lightheadedness, syncope episodes, or any perceived changes in heart rate.
• Advise patients to speak to their healthcare provider if they become pregnant, intend to become pregnant, or are breastfeeding.
• Tell patients to report all concurrent prescription and nonprescription medications or herbal products they are taking.

Frequently asked questions

• Can you take ondansetron while pregnant?

More about ondansetron

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• Drug images
• Side effects
• Patient tips
• During pregnancy
• Support group
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Patient resources

• Drug Information
• Ondansetron injection
• Ondansetron (Injection) (Advanced Reading)
• Ondansetron (Oral, Oromucosal) (Advanced Reading)
• Ondansetron Oral Soluble Film

Other brands

Zofran, Zofran ODT, Zuplenz

Professional resources

• Prescribing Information

Related treatment guides

• Gastroenteritis
• Nausea/Vomiting
• Alcohol Use Disorder
• Nausea/Vomiting, Chemotherapy Induced

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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Ondansetron Interactions Checker – Drugs.com

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There are 338 drugs known to interact with
ondansetron, along with
2 disease interactions.

Of the total drug interactions,
122 are major, 212 are moderate, and 4 are minor.

Does ondansetron interact with my other drugs?

Enter other medications to view a detailed report.

• View all 338 medications that may interact with ondansetron
• View ondansetron disease interactions (2)

Most frequently checked interactions

View interaction reports for ondansetron and the medicines listed below.

• Major
• Moderate
• Minor
• Unknown

• Adderall (amphetamine / dextroamphetamine)
• Aspirin Low Strength (aspirin)
• Benadryl (diphenhydramine)
• Cymbalta (duloxetine)
• Eliquis (apixaban)
• Fish Oil (omega-3 polyunsaturated fatty acids)
• Flexeril (cyclobenzaprine)
• Flonase (fluticasone nasal)
• Lexapro (escitalopram)
• Linzess (linaclotide)
• Lyrica (pregabalin)
• Metoprolol Succinate ER (metoprolol)
• Metoprolol Tartrate (metoprolol)
• MiraLAX (polyethylene glycol 3350)
• Nexium (esomeprazole)
• Norco (acetaminophen / hydrocodone)
• Paracetamol (acetaminophen)
• ProAir HFA (albuterol)
• Probiotic Formula (bifidobacterium infantis / lactobacillus acidophilus)
• Singulair (montelukast)
• Symbicort (budesonide / formoterol)
• Synthroid (levothyroxine)
• Tylenol (acetaminophen)
• Ventolin HFA (albuterol)
• Vitamin B12 (cyanocobalamin)
• Vitamin C (ascorbic acid)
• Vitamin D2 (ergocalciferol)
• Vitamin D3 (cholecalciferol)
• Xanax (alprazolam)
• Zyrtec (cetirizine)

Ondansetron disease interactions

There are 2 disease interactions with ondansetron which include:

• QT interval prolongation
• liver disease

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More about ondansetron

• ondansetron consumer information
• Compare alternatives
• Pricing & coupons
• Reviews (474)
• Drug images
• Side effects
• Dosage information
• Patient tips
• During pregnancy
• Support group
• Drug class: 5HT3 receptor antagonists
• Breastfeeding

Related treatment guides

• Gastroenteritis
• Nausea/Vomiting
• Alcohol Use Disorder
• Nausea/Vomiting, Chemotherapy Induced

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.

Major	Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate	Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor	Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown	No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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Ondansetron PJSC SPC “Borshchagovsky CPP”

• Pharmacological properties
• Indications Ondansetron
• Application of Ondansetron
• Contraindications
• Side effects
• Special instructions
• Interactions
• Overdose
• Storage conditions
• Diagnosis
• Recommended alternatives
• Trade names

Pharmacodynamics. Antiemetic. The mechanism of action is due to a competitive highly selective blockade of central and peripheral 5HT ₃ serotonin receptors (receptors of the trigger zone, vomiting center). Suppresses the gag reflex, eliminating and preventing nausea when using cytotoxic chemotherapeutic agents, radiation therapy, in the postoperative period. With repeated use, it slows down peristalsis and the passage of contents through the intestines.

Pharmacokinetics. When administered intravenously at a dose of 0.15 mg/kg of body weight to adults under the age of 75 years, C _max in blood plasma averages about 100 ng/ml, in persons over the age of 75 years – 170 ng/ml . With an IV infusion of 32 mg for 15 minutes, C _max reaches 264 ng / ml. With the / m administration of C _max ondansetron in blood plasma (about 25 ng / ml) is noted 10 minutes after injection.

When taken orally, the drug is well absorbed in the gastrointestinal tract, bioavailability is about 60% due to the effect of the first passage through the liver. C _max of ondansetron in plasma is reached after 1.5–1.7 hours. Eating prolongs the absorption period by 17% without affecting C _max . Binding to plasma proteins – 70-76%.

The main part of the administered dose (85–90%) is hydroxylated in the liver with the participation of cytochrome P450 to indole ring compounds, and then conjugated with glucuronic and sulfuric acids. The total volume of distribution is 1.9 l / kg of body weight, T _½ , depending on age, is 3.5–5.5 h, the total clearance is 5.9ml/(min kg). The drug is excreted from the body by the kidneys, while 5% of the administered dose is excreted unchanged. The pharmacokinetic parameters of ondansetron do not change with repeated use.

In children, as well as in persons with liver damage, the total clearance decreases, in elderly patients, T _½ and the total clearance of the drug increase. In patients with moderate renal insufficiency (creatinine clearance – 15-60 ml / min), systemic clearance and volume of distribution of ondansetron are reduced, resulting in a clinically insignificant small increase in T _½ drugs. In women, C _max and the bioavailability of the drug are higher, and the clearance and volume of distribution are lower than in men.

prevention and management of nausea and vomiting during cytotoxic chemotherapy (initial and repeated courses, including high dose cisplatin) and radiotherapy (whole body irradiation, partial single high-dose or daily abdominal irradiation) in oncology. Prevention and elimination of nausea and vomiting in the postoperative period in general surgery, ophthalmology, etc.

Tablets

When carrying out cytostatic therapy, the dosing regimen is set individually, depending on the severity of the emetic reaction.

Moderate emetogenic chemotherapy and radiotherapy

Adults and children over 12 years of age, by mouth: Initially 8 mg 1 to 2 hours before anticancer therapy, followed by another 8 mg 8 to 12 hours later. To prevent late or prolonged nausea and vomiting after the first 24 hours, the use of the drug should be continued at 8 mg every 12 hours. With partial high-dose irradiation of the abdominal region, 8 mg every 8 hours is prescribed. The drug is taken during the entire course of chemotherapy and radiation therapy, as well as 1-2 days (if necessary – 3-5 days) after its completion.

Highly emetogenic chemotherapy

Adults and children over 12 years of age are given ondansetron 24 mg orally (simultaneously with dexamethasone phosphate) 1 to 2 hours before starting chemotherapy. For the prevention of late vomiting in the following days, 8 mg 2 times a day during the entire course of chemotherapy, as well as 5 days after its completion.

In case of chemotherapy in children aged 4-12 years, it is prescribed orally: initially 4 mg 3 times a day (30 minutes before the start of the course, then after 4 and 8 hours). To prevent late vomiting, 4 mg is prescribed every 8 hours 1-2 days, then 4 mg 2 times a day during the entire course, as well as 5 days after its completion.

Postoperative nausea and vomiting

Adults and children over 12 years of age are given 16 mg 1 hour before anesthesia. Children under the age of 12 are not prescribed.

The maximum daily dose of ondansetron is 32 mg, for patients with severe hepatic impairment – 8 mg.

Injection solution

The preparation in the form of an injection solution can be administered IM or IV as a single slow injection or by infusion. To prepare the ondansetron solution for infusion, you can use 0.9% sodium chloride solution, 5% glucose solution, Ringer solution. Solution of ondansetron for infusion administration is prepared immediately before administration; however, if necessary, it can be stored until fully used for no more than 24 hours at a temperature of 2–8 °C. During the infusion, protection from light is not required (under normal lighting).

Emethogenic Chemotherapy and Radiation Therapy

For adults, administer 8 mg IV slowly immediately prior to chemotherapy.

Highly emetogenic chemotherapy

• a single dose of 8-32 mg given IV slowly immediately before chemotherapy; when administered at a dose above 8 mg, ondansetron must be dissolved in 50-100 ml of 0. 9% sodium chloride solution or other compatible solution for intravenous administration and an infusion should be carried out for at least 15 minutes;

• a dose of 8 mg is administered slowly IV just before the course of chemotherapy, then 2 IV doses of 8 mg slowly at a dose of 2-4 hours apart, or IV drip at a dose of 1 mg/hour for 24 hours.

The choice of dosing regimen is set individually depending on the severity of the emetogenic effect.

Children may be given a single IV dose of 5 mg/m ² immediately prior to chemotherapy.

Postoperative nausea and vomiting

Adults: 4 mg may be given as a slow IV or IM injection during induction of anesthesia. To eliminate the development of postoperative nausea and vomiting, a single injection of 4 mg intramuscularly or intravenously is recommended.

Children: may be given at a dose of 0.1 mg/kg body weight (maximum 4 mg) IV slowly before, during, or after initiation of anesthesia to prevent postoperative nausea and vomiting. To eliminate the development of postoperative nausea and vomiting, a single dose of 0.1 mg/kg (maximum 4 mg) intramuscularly or intravenously is recommended.

hypersensitivity to drug components; the period of pregnancy (especially the first trimester) and breastfeeding; insufficiency of liver function, surgical operations on the abdominal cavity; the drug is not prescribed to children under the age of 4 years during chemotherapy and radiation therapy; during anesthesia, tablets cannot be prescribed to children under the age of 12 years; injection solution – up to 2 years.

from the side of the central nervous system: headache, dizziness, temporary impairment of visual acuity (with rapid intravenous administration), spontaneous movement disorders, seizures, depression of the central nervous system, paresthesia, weakness, extrapyramidal symptoms, syncope;

from the side of the cardiovascular system: feeling of heat and flushing to the face, arrhythmia, tachycardia or bradycardia, arterial hypo- or hypertension;

from the digestive system: constipation, diarrhea, hiccups, dry mouth, transient increase in aminotransferase activity, liver failure;

allergic reactions: urticaria, bronchospasm, in isolated cases – anaphylactic reactions;

other: cough, chest pain (anginal type), redness and burning at the injection site.

Breast-feeding should be discontinued during treatment with Ondansetron.

For parenteral use of the drug in patients with moderate and severe hepatic impairment, it is not recommended to exceed a dose of 8 mg / day.

In the event of a very severe vomiting reaction as a result of chemotherapy, the effectiveness of the drug can be increased by a single intravenous administration of corticosteroids (for example, 20 mg of dexamethasone sodium phosphate) before starting chemotherapy.

Use with caution in patients with a history of hypersensitivity reactions to other selective serotonin 5HT ₃ receptor antagonists. With caution and under close medical supervision, the drug is used in the treatment of patients with signs of subacute intestinal obstruction.

Simultaneous use of inhibitors of microsomal hepatic enzymes of the cytochrome P450 system can increase T _½ and reduce the overall clearance of the drug.

with special use with inducers of microsomal hepatic enzymes of the P450 cytochrome system (barbiturates, carbamazepine, karizopoli, gluthetimide, Grisoofulvin, nitrogen oxide, papaverine, phenylbutazone, phenytoine, hydrantin, rifampicin, tolbutamide, it is possible to reduce clinical effects of clinical effect the drug.

The drug in the form of an infusion solution at a concentration of ondansetron 16-160 mcg / ml (8 mg / 500 ml – 8 mg / 50 ml) can be administered through a Y-shaped catheter in combination with the following drugs:

• cisplatin up to 0.48 mg/ml for 1-8 hours;

• carboplatin at a concentration of 0.18-9.90 mg / ml for 10-60 minutes;

• fluorouracil at concentrations up to 0.8 mg/ml at a rate of at least 20 ml/h, bearing in mind that higher concentrations of fluorouracil may cause precipitation of ondansetron;

• etoposide at a concentration of 0.14-0.25 mg / ml for 30-60 minutes;

• ceftazidime 0.025-2 g, diluted with water for injection according to manufacturer’s recommendations, as an IV bolus injection over 5 minutes;

• cyclophosphamide 0.1-1 g, diluted with water for injection according to manufacturer’s recommendations, as an IV bolus injection over 5 minutes;

• doxorubicin 10-100 mg, diluted with water for injection according to manufacturer’s recommendations, as an IV bolus injection over 5 minutes;

• Dexamethasone 20 mg IV slowly over 2-5 minutes in combination with 8-32 mg ondansetron in 50-100 ml solution.

The drug should not be used in the same syringe or in the same dropper with other drugs.

Overdose may cause side effects. Treatment is drug withdrawal and symptomatic therapy aimed at maintaining vital functions. There is no specific antidote.

tablets – in a dry, dark place at a temperature not exceeding 25 ° C; ampoules – in a place protected from light at a temperature not exceeding 25 °C. Shelf life – 2 years.

Use of ondansetron in the treatment of children with cancer

Supportive care

Trademarks:

Zofran®

Other names:

Ondansetron Hydrochloride

Often used for:

treatment of nausea and vomiting

Ondansetron is a drug that is used to prevent and treat nausea and vomiting during chemotherapy and radiation therapy, as well as in the postoperative period.

The breakdown rate of ondansetron in the body may vary. This is determined by the activity of an enzyme called P450 2D6 (CYP2D6). Genetic analysis may be required to determine the quality of the enzymes in a particular patient. The drug may not be effective enough if the rate of breakdown of ondansetron in the patient’s body is higher than normal.

This drug is usually taken 30 minutes before chemotherapy starts.

Oral administration in the form of tablets or absorbable films or tablets

Oral liquid form

Administered intravenously (by drip or injection) in liquid form

• Headache
• Pain in the abdomen
• Dizziness
• Diarrhea
• Constipation
• Rash
• Increased fatigue or general weakness
• Blurred vision
• Alarm
• Disorders of the heart
• Liver disorders

The listed side effects are not observed in all patients who are prescribed ondansetron. The most common side effects are highlighted in bold, but others are not excluded. Report all possible side effects to your doctor or pharmacist.

Be sure to discuss these and other recommendations with your doctor or pharmacist.

Taking ondansetron at home:

• Non-absorbable tablets should be swallowed whole. Do not crush or chew before taking.
• Resorbable tablets or films hold on the tongue until completely dissolved. They should not be chewed or swallowed with water or other liquid. Hands must be dry when handling the preparation.
• When taking ondansetron in liquid form, measure the dosage using the measuring device included in the kit.
• Take your dose as soon as possible if you miss it. Do not do this only if there is little time left until the next appointment. In no case do not double the dose at the next dose!
• Store at room temperature. Ondansetron for intravenous administration should be stored in the refrigerator.