From the Guidelines
Retching and vomiting are distinct physiological processes, with retching being the forceful contraction of abdominal and chest muscles that precedes vomiting, but without the actual expulsion of stomach contents, as seen in cyclic vomiting syndrome (CVS) where patients experience recurrent, acute episodes of vomiting and retching 1.
Key Differences and Clinical Implications
- Retching involves rhythmic contractions of the diaphragm and abdominal muscles against a closed glottis, creating the characteristic heaving motion.
- Vomiting is the actual expulsion of stomach contents through the mouth, which follows retching when the lower esophageal sphincter relaxes and stomach contents are forced upward.
- Both processes are controlled by the vomiting center in the medulla oblongata of the brain and can be triggered by various stimuli including toxins, medications, motion sickness, or gastrointestinal irritation, as noted in the diagnosis and management of CVS 1.
- In CVS, approximately 65% of patients experience prodromal symptoms before the onset of vomiting, which can include an impending sense of doom, panic, and multiple constitutional, cognitive, or affective symptoms 1.
Treatment and Management
- Treatment for both retching and vomiting typically involves addressing the underlying cause.
- Antiemetics may be used to manage symptoms, but the specific treatment should be guided by the underlying diagnosis, such as CVS, where recognizing the diagnostic clues and clinical severity is crucial for effective management 1.
- Persistent retching without vomiting can be particularly exhausting and may cause complications, while repeated vomiting can lead to dehydration, electrolyte imbalances, and aspiration pneumonia if stomach contents enter the lungs.
From the Research
Retching vs Vomiting
- Retching and vomiting are two related but distinct symptoms that can have various causes and consequences 2.
- Vomiting is the forcible expulsion of stomach contents, while retching is the involuntary contraction of the abdominal muscles and diaphragm that often precedes vomiting 2.
- The difference between retching and vomiting can be important in diagnosing and treating underlying conditions, such as gastroenteritis, foodborne illness, or medication side effects 2, 3.
Causes and Consequences
- Both retching and vomiting can lead to fluid and electrolyte imbalances, which can be severe and even life-threatening if left untreated 4.
- Certain medications, such as ondansetron and metoclopramide, can be used to treat nausea and vomiting, but may also have side effects and interact with other medications 5, 6.
- In some cases, vomiting can be a symptom of a more serious underlying condition, such as acquired long QT syndrome, which can increase the risk of cardiac arrest 3.
Treatment and Management
- Treatment of retching and vomiting typically involves addressing the underlying cause, as well as providing supportive care such as fluid and electrolyte replacement 2, 4.
- Antiemetic medications, such as ondansetron and metoclopramide, can be effective in reducing symptoms of nausea and vomiting, but may not always be necessary or appropriate 5, 6.
- In some cases, non-pharmacologic management options, such as small, frequent meals and avoidance of trigger foods, may be recommended 2.