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Compare Palonosetron vs. Ondansetron

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Palonosetron (Aloxi) and ondansetron (Zofran) are both antiemetic medications used to prevent nausea and vomiting caused by chemotherapy and surgery. They belong to the same drug class, serotonin antagonists, and work by blocking serotonin in the brain. However, they differ in several ways. Palonosetron is only available as an intravenous (IV) injection, while ondansetron can be taken orally as tablets, orally disintegrating tablets (ODT), or liquid, and also as an injection. Palonosetron is typically given as a single dose before chemotherapy or surgery, whereas ondansetron is taken multiple times a day. Both medications are available as a lower-cost generic. Common side effects of palonosetron include headache and constipation, while ondansetron can cause headache, fatigue, and constipation or diarrhea. Both medications can interact with other drugs that affect serotonin levels, but ondansetron also has a risk of causing heart rhythm problems.

  • Palonosetron
    Ondansetron (Zofran)
  • Palonosetron
    Ondansetron (Zofran)

  • Summary of Palonosetron vs. Ondansetron

    Summary for Antiemetic
    Prescription only

    Palonosetron is a medication that's used to prevent nausea and vomiting from cancer medications (chemotherapy) and surgery. The dose is usually a one-time injection through the veins that's given by a healthcare provider in a clinic or hospital. The most common side effects are headache and constipation. Palonosetron is still available as a generic medication, but its brand name Aloxi is now discontinued.

    Summary for Antiemetic
    Prescription only

    Ondansetron (Zofran) is an antiemetic (or anti-nausea) medication. It's used to prevent nausea and vomiting after surgery or cancer treatments. It works by stopping a chemical called serotonin from binding to receptors in the brain that cause the feeling of nausea and vomiting. Ondansetron (Zofran) is taken by mouth, typically every 8 to 12 hours. It comes in different formulations, including orally disintegrating tablet (ODT) and oral solution. It can also be given as injection by a healthcare professional (HCP) in a hospital setting. Side effects of this medication include headache, tiredness, and constipation or diarrhea.

  • Indications of Palonosetron vs. Ondansetron

    Indications for
    •Prevention of nausea and vomiting from chemotherapy in adults and children 1 month of age and older
    •Prevention of nausea and vomiting (for up to 24 hours) after surgery in adults
    Indications for
    •Prevention of nausea and vomiting due to cancer medications (chemotherapy) or radiation therapy
    •Prevention of nausea and vomiting after surgery

  • Pros and Cons of Palonosetron vs. Ondansetron

    Pros and Const for Antiemetic
    Pros
    •Might work better and have less side effects than other antiemetics in the same drug class
    •Long-lasting medication that's given as a single dose before chemotherapy or surgery
    •Can use for young children age 1 month and older who are receiving chemotherapy
    Cons
    •Can only be given by IV injection (into the vein)
    •Must be given by a healthcare professional
    •Side effects might last a long time
    Pros and Const for Antiemetic
    Pros
    •Can use for both adults and children
    •Available as a lower-cost generic
    •Available as a liquid, dissolvable tablet, and injection for people who have problems swallowing pills or are too nauseous to keep medication down
    •Possible option during pregnancy and breastfeeding
    Cons
    •Needs to be taken multiple times daily
    •Might cause headache
    •Can interact with certain medications, like antidepressants and migraine medications
    •Not the best option for people who are at risk for stomach or gut blockages (bowel problems)

  • Common Side Effects of Palonosetron vs. Ondansetron

    Common Side Effects for
    •Headache (9%)
    •Constipation (5%)
    Common Side Effects for
    •Headache (up to 24%)
    •Fatigue (up to 13%)
    •Constipation (up to 9%)
    •Diarrhea (up to 6%)

  • Warnings of Palonosetron vs. Ondansetron

    Common Side Effects for
    •Allergic reactions
    •Serotonin syndrome
    Common Side Effects for
    •Severe allergic reactions
    •Life-threatening abnormal heart rhythm (QT prolongation)
    •Serotonin syndrome
    •Risk of heart attack
    •Masking of gut blockage and stomach bloating
    •Caution use in people with phenylketonuria (PKU) - orally disintegrating tablets only

  • Prices with our coupons for Palonosetron vs. Ondansetron

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