What can be done to help someone with perpetual nausea?

Management of Perpetual Nausea

Start with dopamine receptor antagonists as first-line therapy: prochlorperazine 10 mg orally every 6 hours or metoclopramide 10-20 mg orally every 6 hours, which are highly effective for most causes of chronic nausea. 1

Initial Assessment: Rule Out Reversible Causes

Before initiating antiemetic therapy, systematically evaluate for specific underlying causes that require targeted treatment:

• Check for medication-induced nausea by reviewing all current medications, particularly opioids, which are a common culprit 1
• Assess for constipation, as this frequently causes or exacerbates nausea and must be addressed first 1
• Evaluate for metabolic abnormalities including hypercalcemia, which can present with persistent nausea 1
• Consider gastrointestinal disorders such as gastritis, gastroesophageal reflux disease, or gastroparesis 1
• Screen for central nervous system pathology, particularly if accompanied by headaches or neurologic symptoms 1

First-Line Pharmacologic Treatment

Begin with dopamine receptor antagonists, which target the chemoreceptor trigger zone and are effective for most nausea etiologies:

• Prochlorperazine 10 mg orally every 6 hours as needed is a phenothiazine with proven efficacy 1, 2
• Metoclopramide 10-20 mg orally every 6 hours provides both antiemetic and prokinetic effects 1
• Haloperidol 0.5-1 mg orally every 6-8 hours is an alternative dopamine antagonist with fewer anticholinergic effects 1

Escalation Strategy for Persistent Nausea

If nausea persists despite as-needed dosing:

• Administer antiemetics around-the-clock for 1 week, then reassess and adjust to as-needed dosing if symptoms improve 3, 1
• Add medications with different mechanisms of action rather than switching between similar agents, as this provides synergistic benefit 3

Second-Line: Add Serotonin Receptor Antagonists

Ondansetron 8 mg orally once or twice daily is highly effective when added to dopamine antagonists:

• Serotonin (5-HT3) antagonists have lower rates of central nervous system side effects compared to dopamine antagonists 3
• The combination of metoclopramide with ondansetron provides particularly effective relief through complementary mechanisms 4, 1
• Ondansetron is FDA-approved for prevention of nausea and vomiting, with established safety profile 5

Additional Adjunctive Options

For refractory symptoms, consider adding:

• Corticosteroids (dexamethasone 2-8 mg orally or IV) are particularly beneficial when combined with metoclopramide and ondansetron 3, 1
• Anticholinergic agents (scopolamine transdermal patch 1 mg/3 days) target vestibular pathways 1
• Olanzapine 2.5-5 mg orally may be especially helpful if bowel obstruction is suspected 3, 1

Management of Truly Refractory Nausea

If symptoms persist beyond one week of scheduled antiemetics:

• Reassess the underlying cause thoroughly, as persistent nausea suggests either an undiagnosed condition or inadequate treatment of the primary cause 3, 1
• Consider cannabinoids (dronabinol or nabilone) for refractory nausea, particularly if chemotherapy-related 3, 1
• Evaluate for gastroparesis and consider prokinetic agents if gastric emptying is delayed 1

Critical Pitfalls to Avoid

• Do not ignore persistent nausea complaints, as this leads to poor quality of life and may mask serious underlying conditions 4
• Do not use antiemetics in patients with known or suspected mechanical bowel obstruction without appropriate evaluation, as they may mask progressive ileus 3
• Monitor for serotonin syndrome when combining serotonergic medications, particularly ondansetron with other serotonergic drugs 5
• Screen for QT prolongation in patients receiving ondansetron, especially those with cardiac risk factors or on other QT-prolonging medications 5

Special Considerations for Gastric Causes

If gastritis or reflux is contributing:

• Use proton pump inhibitors or H2 receptor antagonists to address acid-related nausea 1
• For gastric outlet obstruction, consider corticosteroids or procedural interventions 1