• Clinical science

Antiemetics

Abstract

Antiemetics are a heterogeneous group of drugs used to treat various causes of nausea and vomiting. Different antiemetics act on different receptors, and they may have a peripheral effect, a central effect, or both. Whereas serotonin antagonists, for example, bind 5-HT3 receptors and effectively combat cytotoxic drug nausea, certain anticholinergic drugs target M1 receptors and specifically treat motion sickness (kinetosis). Hospitals and clinics commonly use the dopamine D2 antagonist metoclopramide. However, because of its strong central effect and possible extrapyramidal side effects, metoclopramide must be used with caution.

Overview

Group Drug Antagonized receptor Mechanism Specific features Side effects
Dopamine receptor antagonists/ prokinetic agents

Prochlorperazine

D2
Domperidone

Metoclopramide

  • Antiemetic effect at the area postrema
  • Prokinetic effect : Increased gastric contractions, duodenal and jejunal motility, resting tone of the lower esophageal sphincter and decreased pylorus sphincter activity allow food to pass more quickly through the stomach and the small intestine.
Serotonin receptor antagonists Ondansetron (Zofran®) 5-HT3
  • Central-acting antiemetic effect
  • Peripheral inhibition of the intestinal tract's vagal nerve signals
  • Especially effective against chemotherapy and radiation-induced vomiting and postoperative nausea and vomiting (PONV)
Anticholinergic agents Scopolamine M1
  • Antiemetic effect at the area postrema and on the vestibular system
  • Peripheral inhibition of the intestinal tract's vagal nerve signals
  • Especially effective against motion sickness or vestibular-induced nausea and vomiting
Antihistamines Meclizine, dimenhydrinate, diphenhydramine,doxylamine, promethazine H1
  • Antiemetic effect in the CNS

Neurokinin receptor antagonists

Aprepitant NK1
  • Antiemetic effect in the CNS
  • CYP enzyme inhibition cause numerous interactions with other drugs.
  • Fatigue
  • Hiccups
Glucocorticoids Dexamethasone
  • Unknown mechanism
  • Used especially against PONV and usually in combination with other substances

References:[1][1][1][2][2][2][2][3][4][5][6][7][8][9]

Indications

References:[2][10][5]

Contraindications

References:[10][5][7]

We list the most important contraindications. The selection is not exhaustive.

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last updated 11/19/2018
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