Zofran (Ondansetron)

Description

Zofran is a 5-HT3 receptor antagonist that is taken to prevent nausea and vomiting due to:

• Highly-emetogenic chemotherapy
• Moderately emetogenic chemotherapy
• Radiotherapy, including total body irradiation, single high-dose abdominal fraction, or daily abdominal fractions
• Postoperative

The generic name for Zofran is Ondansetron.

Directions

Once you are prescribed and buy Zofran, then Zofran is available in 4 mg and 8 mg oral tablets and orally disintegrating tablets (ODT). Zofran is also available in a 4 mg/5 mL oral solution.

Recommended Zofran dosage regimen for adults:

• Highly emetogenic chemotherapy: 24-mg dose given 30 minutes before receiving chemotherapy.
• Moderately emetogenic chemotherapy: 8-mg dose given 30 minutes before receiving chemotherapy. Another 8-mg dose is given 8 hours after the first dose, then 8 mg every 12 hours for 1 to 2 days after chemotherapy.

• Total body irradiation: 8-mg dose given 1 to 2 hours before each fraction of radiotherapy.
• Single high-dose abdominal fraction: 8-mg dose given 1 to 2 hours before radiotherapy, then 8 mg every 8 hours after the first dose for 1 to 2 days after completing radiotherapy.
• Daily abdominal fraction: 8-mg dose given 1 to 2 hours before radiotherapy, then 8 mg given every 8 hours after the first dose for each day radiotherapy is administered.
• Postoperative: 16-mg dose given 1 hour before anesthesia.

Recommended Zofran dosage regimen for pediatrics:

• Moderately emetogenic chemotherapy for patients 12 to 17 years of age: 8-mg dose given 30 minutes before chemotherapy. Another 8 mg is given at 4 and 8 hours after the first dose, then 8 mg three times a day for 1 to 2 days after chemotherapy.
• Moderately-emetogenic chemotherapy for patients 4 to 11 years of age: 4-mg dose given 30 minutes before chemotherapy. Another 4 mg is given at 4 and 8 hours after the first dose, then 4 mg three times a day for 1 to 2 days after chemotherapy. 

If you have severe liver problems, you should not take more than 8 mg of Zofran per day.

Ingredients

The active ingredient in Zofran is Ondansetron.

Contraindications

Be sure you speak to your doctor about your allergies. Do not take Zofran if you are allergic to ondansetron or any of the ingredients in Zofran.

Do not take Zofran with apomorphine.

Cautions

• Some medications may interact with Zofran if taken together. Tell your doctor if you take any other medications, including prescription, over-the-counter, herbal supplement, and vitamins.
• Stop Zofran immediately if you develop an allergic reaction, including anaphylaxis and bronchospasm. Seek medical care right away if you have a rash, hives or swelling, trouble breathing, tightness of the throat, or a fast heartbeat.
• Do not take Zofran if you have congenital long QT syndrome. The risk for QT prolongation and Torsades de Pointes is increased if you take Zofran with other medications that can prolong the QT interval and should be monitored with electrocardiograms. You should also be monitored if you have certain electrolyte abnormalities, heart failure, or arrhythmias. 
• Zofran may increase your risk for serotonin syndrome, especially if taken with other serotonergic medications. Serotonin syndrome can be life-threatening. Seek medical care right away if you experience agitation, confusion, dilated pupils, high blood pressure, fast heart rate, rigid muscles, diarrhea, headache, shivers, loss of muscle coordination or twitching muscles, sweating, goosebumps, fever, or seizures.
• Zofran may mask progressive ileus or gastric distention in patients who have had abdominal surgery or chemotherapy-induced nausea and vomiting. Monitor for decreased bowel activity, especially in patients who have risk factors for gastrointestinal obstruction.
• Phenylketonuric patients should be cautioned that Zofran ODT (orally disintegrating tablets) contain phenylalanine.
• Tell your doctor if you are pregnant or plan to become pregnant. Consider the benefits versus risks.
• Tell your doctor if you are breastfeeding or plan to breastfeed. The benefits versus risks should be considered.

Side Effects

Zofran may cause side effects. Tell your doctor if you experience severe adverse effects or side effects that are bothersome or won't go away. Common Zofran side effects may include:

• Headache
• Fatigue
• Diarrhea
• Constipation

You can order Zofran (ondansetron) at competitive pricing online with a prescription from Canada Drugs Direct.

References:

1. ZOFRAN Prescribing Information. Research Triangle Park, NC: GlaxoSmithKline; 2016.
2. Serotonin syndrome. Mayo Clinic. December 10, 2019. Accessed November 18, 2021.