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Compare Phenergan vs. Aloxi

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

Key takeaways

Promethazine (Phenergan) and Palonosetron (Aloxi) are both used to treat nausea and vomiting, but they work differently and have different uses. Promethazine is an antihistamine that also blocks dopamine and acetylcholine, making it useful for allergies, motion sickness, and pre-surgery relaxation. It comes in various forms, including tablets, syrup, suppositories, and injections. Palonosetron, on the other hand, is a serotonin antagonist specifically used to prevent nausea and vomiting from chemotherapy and surgery. It is only available as an injection and must be administered by a healthcare professional. Promethazine can cause drowsiness and dizziness, while Palonosetron's common side effects include headache and constipation. Promethazine is not recommended for children under 2 years old due to serious breathing risks, whereas Palonosetron can be used in children as young as 1 month for chemotherapy-related nausea.

  • Promethazine
    Palonosetron
  • Promethazine
    Palonosetron

  • Summary of Phenergan vs. Aloxi

    Summary for Antihistamine
    Prescription only

    Promethazine is a prescription medication with many uses, such as treatment or prevention of nausea, motion sickness, and allergy symptoms. Promethazine works by blocking several chemicals, including histamine, dopamine, and acetylcholine. It comes as tablets, an oral solution, rectal suppositories, and an injection. The dose of promethazine and how often you take it depends on your age and what medical condition you're taking it to treat. But it shouldn't be given to children younger than 2 years of age since it can cause serious breathing problems. Common side effects include sleepiness and dizziness.

    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.

  • Indications of Phenergan vs. Aloxi

    Indications for
    •Runny nose, watery eyes, and other symptoms of allergies
    •Runny or stuffy nose that isn't caused by allergies
    •Rash, swelling, anaphylaxis, and other symptoms of an allergic reaction
    •Dermographism
    •Treatment or prevention of nausea and vomiting before and after surgery
    •Treatment or prevention of motion sickness
    •Treatment of pain along with other pain medications after surgery
    •Help to relax your body and produce a light sleep, particularly before a procedure
    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

  • Pros and Cons of Phenergan vs. Aloxi

    Pros and Const for Antihistamine
    Pros
    •Available as a lower-cost generic
    •Available in different formulations, such as a tablet, syrup, and injection
    •Starts working within 20 minutes
    Cons
    •Can't be taken by children under 2 years old because risk of serious breathing problem
    •Higher risk of side effects in older adults
    •Can cause sleepiness
    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

  • Common Side Effects of Phenergan vs. Aloxi

    Common Side Effects for
    •Feeling drowsy or tired
    •Dizziness
    •Confusion
    •Dry mouth
    •Nervousness
    •Blurry vision

    The following side effects are those additionally reported with promethazine injection at the injection site:

    •Burning
    •Pain
    •Rash
    •Swelling
    Common Side Effects for
    •Headache (9%)
    •Constipation (5%)

  • Warnings of Phenergan vs. Aloxi

    Common Side Effects for
    •Potentially life-threatening slow breathing (respiratory depression)
    •Serious tissue injury (Injection only)
    •Excessive sleepiness
    •Worsening of certain health problems
    •Seizures
    •Higher risk of infection (from low white blood cell count)
    •Risk of serious nerve problems (neuroleptic malignant syndrome)
    •Uncontrollable body movements
    Common Side Effects for
    •Allergic reactions
    •Serotonin syndrome

  • Prices with our coupons for Phenergan vs. Aloxi

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