Background By understanding the pathophysiology of nausea and targeting antiemetics to specific receptors, therapy can be optimized and side effects minimized. An easy way to remember the causes of vomiting is the VOMIT acronym. In the table below receptors involved in different types of nausea are highlighted using this acronym. Blockade of these receptors allows rational, focused therapy.
Cause – Vestibular
- Receptors Involved – Cholinergic, Histaminic
- Drug Class Useful – Anticholinergic, Antihistaminic
- Drug Examples – Scopolamine patch, Promethazine
Cause – Obstruction of Bowel by Constipation (See FF #294 and #295)
- Receptors Involved – Cholinergic, Histaminic, likely 5HT3
- Drug Class Useful – Stimulate myenteric plexus
- Drug Examples – Senna products
Cause – DysMotility of upper gut
- Receptors Involved – Cholinergic, Histaminic, 5HT3, 5HT4
- Drug Class Useful – Prokinetics which stimulate 5HT4 receptors
- Drug Examples – Metoclopramide
Cause – Infection, Inflammation
- Receptors Involved – Cholinergic, Histaminic, 5HT3, Neurokinin 1
- Drug Class Useful – Anticholinergic, Antihistaminic, 5HT3 antagonists, Neurokinin 1 antagonists
- Drug Examples – Promethazine (e.g. for labyrinthitis), Prochlorperazine
Cause – Toxins stimulating the chemoreceptor trigger-zone in the brain such as opioids (see FF 25) or chemotherapy (see FF #285)
- Receptors Involved – Dopamine 2, 5HT3
- Drug Class Useful – Antidopaminergic, 5HT3 Antagonists
- Drug Examples – Prochlorperazine, Haloperidol, Ondansetron
- 5HT3, 5HT4 refer to the serotonin receptors, subtypes 3 & 4.
- Promethazine and prochlorperazine are very different drugs. Promethazine is most useful for vertigo and gastroenteritis due to infections and inflammation. Prochlorperazine is preferred for opioid related nausea.
- There is no evidence supporting the use of lorazepam as a sole agent for nausea. Sedated patients are more prone to aspiration.
- ‘O’ here relates to ‘obstruction’ of bowels by constipation, not mechanical blockage (see Fast Facts #45, 119 for management of mechanical obstructions).
- See FF #93 & #279 for information on cannibinoids and cannabis for nausea and vomiting
- Glare P, et al. Systemic review of the efficacy of antiemetics in the treatment of nausea in patients with far-advanced cancer. Support Care Cancer. 2004; 12:432-440.
- Hallenbeck J. Palliative Care Perspectives. New York, NY: Oxford University Press; 2003: pp75-86.
Version History: This Fast Fact was originally edited by David E Weissman MD. 2nd Edition published July 2005; 3rd Edition May 2015. Current version re-copy-edited May 2015.
Fast Facts and Concepts are edited by Sean Marks MD (Medical College of Wisconsin) and associate editor Drew A Rosielle MD (University of Minnesota Medical School), with the generous support of a volunteer peer-review editorial board, and are made available online by the Palliative Care Network of Wisconsin (PCNOW); the authors of each individual Fast Fact are solely responsible for that Fast Fact’s content. The full set of Fast Facts are available at Palliative Care Network of Wisconsin with contact information, and how to reference Fast Facts.
Copyright: All Fast Facts and Concepts are published under a Creative Commons Attribution-NonCommercial 4.0 International Copyright (http://creativecommons.org/licenses/by-nc/4.0/). Fast Facts can only be copied and distributed for non-commercial, educational purposes. If you adapt or distribute a Fast Fact, let us know!
Disclaimer: Fast Facts and Concepts provide educational information for health care professionals. This information is not medical advice. Fast Facts are not continually updated, and new safety information may emerge after a Fast Fact is published. Health care providers should always exercise their own independent clinical judgment and consult other relevant and up-to-date experts and resources. Some Fast Facts cite the use of a product in a dosage, for an indication, or in a manner other than that recommended in the product labeling. Accordingly, the official prescribing information should be consulted before any such product is used.