What causes nausea due to medication (adverse drug reaction)?

From the Guidelines

If you're experiencing nausea due to medication, the most effective treatment is ondansetron (Zofran) 4-8mg as needed every 8 hours, as recommended by the most recent and highest quality study 1. This medication is commonly used for medication-induced nausea and has been shown to be effective in reducing symptoms. In addition to ondansetron, other strategies can help alleviate nausea, such as:

• Taking medication with food, unless specifically directed to take it on an empty stomach
• Eating small, frequent meals rather than large ones
• Trying ginger tea, ginger candies, or peppermint tea
• Avoiding strong odors, spicy foods, and fatty foods which can worsen nausea
• Staying hydrated with small sips of clear fluids If nausea is severe, persistent, or accompanied by vomiting that prevents keeping down fluids or medications, it's essential to contact a healthcare provider immediately. They may need to adjust medication dosage, switch to a different medication, or prescribe an anti-nausea medication. Medication-induced nausea occurs because many drugs can irritate the stomach lining or trigger the chemoreceptor trigger zone in the brain that controls vomiting, but symptoms often improve after a few days as the body adjusts to the medication. Other options for managing nausea include:
• Dimenhydrinate (Dramamine) 50-100mg every 4-6 hours
• Meclizine (Bonine) 25mg every 24 hours
• Metoclopramide, which has both central and peripheral effects and is recommended as first line for the management of chronic nausea, including opioid-related 1
• 5-Hydroxytryptamine3 (5-HT3) receptor antagonists, such as granisetron, which have similar efficacy to ondansetron and can be used as an alternative 1
• Neurokinin (NK-1) receptor antagonists, such as aprepitant, which can be effective in reducing nausea and vomiting, especially in patients with refractory gastroparesis symptoms 1

From the Research

Nausea due to Medication

• Nausea and vomiting are common symptoms that can be caused by various factors, including medication adverse effects 2
• A practical 5-step approach to evaluating and treating nausea and vomiting includes considering medication or toxin adverse effects as a potential cause 2
• Antiemetic drugs can be used to manage nausea and vomiting, and the choice of drug depends on the underlying cause of the symptoms 3
• Common antiemetic classes include serotonin, dopamine, histamine, muscarinic, and neurokinin antagonists, as well as corticosteroids and benzodiazepines 3

Management of Nausea due to Medication

• For acute or mild nausea and vomiting, an empirical trial of antiemetics may be sufficient without extensive testing 2
• For chronic or moderate-severe nausea and vomiting, testing for an underlying cause should be performed, and medication adverse effects should be considered 2
• Ondansetron and metoclopramide are commonly used antiemetics, but their effectiveness may vary depending on the specific cause of nausea and vomiting 4, 5
• The choice of antiemetic drug should be guided by the underlying cause of nausea and vomiting, as well as the patient's individual needs and medical history 3

Specific Antiemetic Drugs

• Ondansetron is a serotonin antagonist that is highly effective in treating chemotherapy-induced nausea and vomiting 3
• Metoclopramide is a dopamine antagonist that can be used to treat nausea and vomiting, but it may cause extrapyramidal adverse effects, particularly in children 3
• A study comparing ondansetron and metoclopramide found similar reductions in nausea severity, but the difference from placebo did not reach significance 4
• Another study found that ondansetron and metoclopramide had similar effectiveness in treating nausea and vomiting in pregnancy, but the trial was unable to provide conclusive evidence due to slow recruitment 5