How to manage new onset nausea after starting gabapentin (Neurontin)?

Management of Nausea After Starting Gabapentin

For patients experiencing new onset nausea after starting gabapentin, dopamine receptor antagonists such as metoclopramide, prochlorperazine, or haloperidol should be used as first-line treatment. 1, 2

First-Line Management

• Assess for other causes of nausea (e.g., constipation, CNS pathology, electrolyte disturbances) before attributing solely to gabapentin 1
• Begin with dopamine receptor antagonists:
  • Metoclopramide 10-20 mg PO/IV every 6 hours 1
  • Prochlorperazine 10 mg PO/IV every 6 hours 1
  • Haloperidol 0.5-1 mg PO every 6-8 hours 1

If Nausea Persists

• Switch from as-needed dosing to scheduled administration of antiemetics around the clock for 1 week, then change back to as-needed dosing 1
• Consider adding medications with different mechanisms of action:
  • Serotonin (5-HT3) receptor antagonists such as ondansetron 8 mg PO/IV or granisetron 1-2 mg PO daily 1
  • Corticosteroids such as dexamethasone 4-12 mg PO/IV daily can be beneficial, particularly in combination with other antiemetics 1

Evidence for Gabapentin and Nausea

• While gabapentin commonly causes nausea as a side effect, particularly when initiating therapy, some studies paradoxically show gabapentin may have antiemetic properties in certain contexts:
  • Gabapentin has shown efficacy in reducing chemotherapy-induced nausea and vomiting when used as an adjunctive therapy 3, 4
  • In a small study of patients with hyperemesis gravidarum, gabapentin was associated with significant reductions in nausea and vomiting 5, 6
  • Gabapentin has demonstrated effectiveness in preventing postoperative nausea and vomiting 7

If Nausea Continues Despite Treatment

• Reassess the cause and severity of nausea 1
• Consider opioid rotation if gabapentin was prescribed for pain management and other measures have failed 1
• Consider dose reduction of gabapentin or slower titration schedule 8
• If severe and persistent despite multiple interventions, consider discontinuation of gabapentin and switching to an alternative medication 1

Prevention Strategies

• For patients with prior history of medication-induced nausea, prophylactic treatment with antiemetics is highly recommended before starting gabapentin 1, 2
• Slower titration of gabapentin dosing may help reduce the incidence of nausea 8
• Taking gabapentin with food may help reduce gastrointestinal side effects 8

Common Pitfalls to Avoid

• Failing to rule out other causes of nausea, particularly constipation, which is another common side effect of gabapentin 1
• Not providing adequate hydration, which can worsen nausea symptoms 2
• Discontinuing gabapentin abruptly, which can lead to withdrawal symptoms including increased nausea 8
• Using only one class of antiemetics when a combination approach targeting different pathways may be more effective 1