Ondansetron: functions, dosage, side effects, how to use

What Drug Ondansetron?

What is ondansetron for?

Ondansetron is a drug to prevent nausea and vomiting caused by cancer treatments, such as chemotherapy and radiation therapy (radiotherapy).

This drug is also used to prevent and treat vomiting after surgery. Ondansetron can be used alone or in combination with other medicines.

The way this drug works is by blocking the serotonin in the body that causes vomiting. Ondansetron is a drug that belongs to a class of drugs named 5-HT3 blockers.

Ondansetron dosage

How do I use ondansetron?

Ondansetron is a drug that dissolves on the tongue. This medicine is not for chewing or swallowing like other tablets. This medication may be packaged in a bottle or strip.

Make sure your hands are completely dry before touching this medicine. If using a strip pack, peel the back of the strip to remove the tablet. Do not push the tablet through the strip cover layer.

As soon as the tablet is removed, place it on the tongue. Let it dissolve completely, then swallow it up. Do not swallow this medicine with water as this will increase your risk of developing a headache.

Take this drug 30 minutes before starting therapy to prevent nausea due to chemotherapy. To prevent nausea from radiation treatment, take this medication 1-2 hours before starting treatment. To prevent nausea after surgery, take this drug 1 hour before starting surgery.

This medicine may be taken with or without food. However, your doctor may ask you not to eat before chemotherapy, radiation, or surgery.

Use the dosage according to the doctor's instructions. Ondansetron can be taken up to 3 times a day for 1 to 2 days after your chemotherapy or radiation treatment is finished.

If you have been prescribed this drug along with a schedule for taking the medicine, take it regularly for optimal benefits. To help you remember, take it at the same time every day.

Dosage is usually based on your medical condition and your response to therapy. The dosage for children is usually based on age and body weight. In patients with severe liver problems, the maximum dose is 8 mg in 24 hours.

Take this medication exactly as instructed. Do not increase the dose or take it more often than prescribed.

Call your doctor or pharmacist if you have questions. Tell your doctor if your condition persists or gets worse.

How to store this drug?

Ondansetron is a drug that is best stored at room temperature, away from direct light and damp places. Don't keep it in the bathroom. Don't freeze it.

Other brands of this drug may have different storage rules. Observe the storage instructions on the product package or ask your pharmacist. Keep all medicines away from children and pets.

Do not flush medicines down the toilet or down the drain unless instructed to do so. Discard this product when the drug has expired or when it is no longer needed.

Consult your pharmacist or local waste disposal company about how to safely dispose of your medicine.

Ondansetron side effects

The information provided is not a substitute for medical advice. ALWAYS consult your doctor or pharmacist before starting treatment.

What is the dose of ondansetron for adults?

The following are the recommended doses of ondansetron for adults:

Oral ondansetron dosage (tablet that dissolves in the mouth, liquid, or tablet):

For prevention of mild nausea and vomiting after cancer treatment

Adults, teenagers, and children 12 years and over can start with a dose of 8 mg taken 30 minutes before starting cancer treatment.

This 8 mg dose should be taken again 8 hours after the first dose. Then, the dose is 8 mg every 12 hours for 1 to 2 days.

Children 4 to 11 years of age can be started with a dose of 4 mg taken 30 minutes before starting cancer treatment. This 4 mg dose should be taken again 4 hours and 8 hours after the first dose.

Then, the dose is 4 mg every 12 hours for 1 to 2 days. Children under 4 years of age, the dose must be determined by your doctor.

For prevention of severe nausea and vomiting after cancer treatment

Adults, teenagers, and children from 12 years old, please take one 24 mg tablet, taken 30 minutes before starting cancer treatment.

As for children under 12 years of age, the use and dose must be determined by the doctor.

For prevention of nausea and vomiting after radiation treatment

For adults, it can be started with a dose of 8 mg to be consumed 1 to 2 hours before radiation treatment.

Then the dose becomes 8 mg every 8 hours. For children, use and dose must be determined by the doctor.

For prevention of nausea and vomiting after surgery

For adults please take 16 mg one hour before starting the anesthetic. For children, use and dose must be determined by the doctor.

Oral dosage (sheets /soluble film)

For prevention of mild nausea and vomiting after cancer treatment

Adults, teenagers and children 12 years and over. Starting with a dose of 8 mg taken 30 minutes before starting cancer treatment.

The second 8 mg dose is taken again 8 hours after the first dose. Then, a dose of 8 mg is taken twice a day every 12 hours for 1 to 2 days.

Children 4 to 11 years. Starting with a dose of 4 mg taken 30 minutes before starting cancer treatment. This 4 mg dose should be taken again 4 hours and 8 hours after the first dose. Then, the dose is 4 mg every 8 hours for 1 to 2 days.

For prevention of severe nausea and vomiting after cancer treatment

For adults, it can be started with a dose of 24 mg or three 8 mg films taken 30 minutes before starting cancer treatment.

Each film must be allowed to dissolve on the tongue before removing another sheet.

For prevention of nausea and vomiting after radiation treatment

For adults, you can use one dose with a dose of 8 mg of film three times a day

For prevention of nausea and vomiting after surgery

For adults can use a dose of 16 mg, taken 1 hour before anesthesia is given. Each sheet of film must be allowed to dissolve on the tongue before removing the next sheet.

What is the dosage of Ondansetron for children?

The following are the recommended doses of ondansetron for children:

Oral ondansetron dosage (oral dissolved tablet, liquid, or regular tablet)

For prevention of mild nausea and vomiting after cancer treatment

Children 4 to 11 years of age can start with a dose of 4 mg taken 30 minutes before starting cancer treatment. This 4 mg dose should be taken again 4 hours and 8 hours after the first dose.

Then, the dose is 4 mg every 12 hours for 1 to 2 days. Children under 4 years of age, use and dose must be determined by your doctor.

Oral dosage (sheets /soluble film)

For prevention of mild nausea and vomiting after cancer treatment

Children 4 to 11 years of age can be started with a dose of 4 mg taken 30 minutes before starting cancer treatment. This 4 mg dose should be taken again 4 hours and 8 hours after the first dose.

Then, the dose is 4 mg three times a day (every 8 hours) for 1 to 2 days.

In what dosage is this drug available?

Ondansetron is a drug that is available as tablets, liquids and injections in doses of 4 mg and 8 mg.

Ondansetron Drug Warnings and Cautions

What side effects can be experienced due to ondansetron?

Common side effects of ondansetron are:

• Diarrhea or constipation
• Feeling weak or tired
• Fever
• Headache
• Dizziness, drowsiness

Tell your doctor right away if you experience serious side effects, such as:

• Blurred vision or temporary loss of vision (from a few minutes to several hours)
• Severe headache, shortness of breath, fainting, fast and fast heartbeat
• Slow heart rate, difficulty breathing
• Nervousness, tension, chills
• Feel like passing out
• Urinating rarely or not urinating at all

Not everyone experiences the following side effects. There may be some side effects not listed above.

If you have concerns about certain side effects, consult your doctor or pharmacist.

Ondansetron Drug Interactions

What should I know before using ondansetron?

Before using certain drugs, consider the risks and benefits first. This is a decision you and your doctor will have to make. For this drug, pay attention to the following:

Allergy

Tell your doctor if you have any unusual or allergic reactions to this or any other medicine. Also tell your doctor if you have any other types of allergies such as to food, coloring, preservatives, or animal allergies. For over-the-counter products, read the labels on the packaging carefully.

Children

Research on the effect of ondansetron in children under 4 years of age has not been conducted. Safety and efficacy have not been established.

Elderly

The studies conducted to date have not shown any problems that can hinder the effectiveness of ondansetron in elderly patients.

Is this drug safe for pregnant and lactating women?

There are no adequate studies regarding the risks of using ondansetron in pregnant or breastfeeding women. Always consult your doctor to weigh the potential benefits and risks before using this medication.

This drug is included in the risk of pregnancy category B according to the US Food and Drug Administration (FDA). The following references the pregnancy risk categories according to the FDA:

• A = Not at risk
• B = No risk in several studies
• C = May be risky
• D = There is positive evidence of risk
• X = Contraindicated
• N = Unknown

Ondansetron overdose

What medicines may interact with ondansetron?

Although some drugs should not be taken at the same time, in other cases some drugs can also be used together even though interactions may occur.

In such cases, the doctor may change the dose, or take other preventive measures as needed.

Tell your doctor if you are taking any other over-the-counter or prescription drugs.

The following are drugs that have the potential to trigger interactions with ondansetron:

• apomorphine
• fluoxetine
• paroxetine
• phenytoin
• carbamazepine
• rifampin
• rifabutin
• rifapentine

Can food or alcohol interact with this drug?

Certain drugs should not be used with meals or when eating certain foods because drug interactions can occur.

Smoking tobacco or consuming alcoholic beverages with certain drugs can also cause interactions to occur. Discuss your use of drugs with food, alcohol, or tobacco with your health care provider.

What health conditions can interact with ondansetron?

Any other health conditions you have can affect the use of this drug. Always tell your doctor if you have other health problems, especially:

• Bowel congestion
• Gastric distension (enlarged abdomen)
• Congestive heart failure
• Heart rhythm problems (eg longer QT interval, slow heart rate)
• Hypokalemia (low potassium in the blood)
• Hypomagnesemia (low magnesium in the blood)
• Liver disease
• Phenylketonuria

Overdose

What should I do in an emergency or overdose?

In case of an emergency or overdose, contact the local emergency services provider (118/119) or immediately to the nearest hospital emergency department.

Overdose symptoms include:

• Sudden vision loss for a short period of time.
• Dizziness or spinning vision.
• Fainting.
• Constipation.
• Abnormal heart rate.

What should I do if I miss a dose?

If you forget a dose of this medicine, take it as soon as possible. However, when it is nearing the time of the next dose, skip the missed dose and return to the usual dosing schedule. Don't double the dose.