Ondansetron 8mg
Generic For: Zofran
Ondansetron 8mg (generic Zofran) is a prescription antiemetic that helps prevent nausea and vomiting caused by chemotherapy, radiation treatment, and surgery. It works by blocking serotonin signals that trigger the vomiting reflex. Order online and, after review by a licensed provider, your medication ships from a licensed U.S. pharmacy.
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Buy Ondansetron 8mg Tablets Online (Generic Zofran)
Ondansetron is a 5-HT3 receptor antagonist antiemetic used to prevent nausea and vomiting from chemotherapy, radiation therapy, and surgery.
Ondansetron 8mg Quick Facts
| Drug class | 5-HT3 receptor antagonist |
|---|---|
| Treats | Chemotherapy-induced nausea, radiation-induced nausea, postoperative nausea and vomiting |
| Form | Tablet |
| Typical dosing | Take 1 tablet by mouth every 6 hours as needed for nausea. If nausea occurs with food or pills, take 1 tablet 30 minutes before. |
| Prescription required | Yes — prescription only |
What Is Ondansetron 8mg?
Ondansetron is a prescription medication in the 5-HT3 receptor antagonist class, sold under the brand name Zofran. It blocks serotonin, a natural substance that can trigger nausea and vomiting, at receptors in the gut and brain. Ondansetron is most often prescribed to prevent nausea and vomiting caused by cancer chemotherapy, radiation therapy, or surgery. The 8mg tablet is taken by mouth, typically before treatment and on a schedule set by your prescriber.
What Does Ondansetron 8mg Treat?
Prevention of nausea and vomiting from cancer chemotherapy
Prevention of nausea and vomiting from radiation therapy
Prevention of postoperative nausea and vomiting
Prevention of nausea from moderately emetogenic chemotherapy
Prevention of nausea from total body irradiation
Ondansetron 8mg Dosage
Chemotherapy: 8 mg PO 30 minutes before chemotherapy, then 8 mg 8 hours later; then 8 mg PO every 12 hours for 1–2 days after treatment.
Radiation therapy: 8 mg PO 1–2 hours before each fraction of radiation, then every 8 hours as directed.
Postoperative: 16 mg PO 1 hour before induction of anesthesia.
Your prescriber will determine the dose and duration that are right for you. Always follow the directions on your prescription label.
Ondansetron 8mg Side Effects
Common side effects
- Headache
- Constipation
- Diarrhea
- Fatigue or drowsiness
- Dizziness
- Fever
- Dry mouth
Serious side effects
Stop taking this medication and seek medical attention right away if you experience:
- Irregular heartbeat or QT prolongation
- Serotonin syndrome (agitation, rapid heartbeat, fever, muscle stiffness)
- Severe allergic reaction (rash, swelling, trouble breathing)
- Chest pain or fainting
- Signs of bowel blockage (severe abdominal pain, swelling)
Warnings & Interactions
Do not use with apomorphine (risk of severe low blood pressure and loss of consciousness)
Do not use if allergic to ondansetron or other 5-HT3 antagonists
Can prolong the QT interval; avoid in congenital long QT syndrome
Risk of serotonin syndrome when combined with SSRIs, SNRIs, MAOIs, or other serotonergic drugs
May mask a progressive ileus or gastric distention after abdominal surgery
Use caution with electrolyte abnormalities (low potassium or magnesium)
Tell your provider about all heart conditions and current medications
Tell your prescriber about all medications, supplements, and health conditions before starting ondansetron 8mg.
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