Treatment of postoperative nausea and vomiting in adults
Before starting treatment for postoperative nausea and vomiting (PONV), exclude drug or mechanical causes (eg swallowing blood, bowel obstruction).
Treatment of PONV depends on whether prophylactic antiemetic therapy was given, and the regimen used (ie drug choice and timing). Although 5-HT3–receptor antagonists are the only drugs adequately studied for treatment of PONV, other antiemetic drugs are often necessary.
If an antiemetic was not given for prophylaxis, use a 5-HT3–receptor antagonist for treatment1:
1granisetron 0.1 to 1 mg intravenously2 granisetron granisetron granisetron
OR
1ondansetron 1 to 4 mg intravenously2 ondansetron ondansetron ondansetron
OR
1tropisetron 0.5 to 2 mg intravenously2. tropisetron tropisetron tropisetron
If an antiemetic was given for prophylaxis, treat PONV with a drug from a different class to that used for prophylaxis. Options include:
1granisetron 0.1 to 1 mg intravenously granisetron granisetron granisetron
OR
1ondansetron 1 to 4 mg intravenously ondansetron ondansetron ondansetron
OR
1tropisetron 0.5 to 2 mg intravenously tropisetron tropisetron tropisetron
OR
1dexamethasone 2 to 4 mg intravenously dexamethasone dexamethasone dexamethasone
OR
1droperidol 0.5 to 0.625 mg intravenously. droperidol droperidol droperidol
If a 5-HT3–receptor antagonist (other than palonosetron) was used for prophylaxis and longer than 6 hours has elapsed since it was administered, a second dose may provide some benefit, but this should only be considered if there are no alternative treatment options. Re-administration of longer-acting drugs (eg dexamethasone, palonosetron) is not recommended.
If PONV persists, use an alternative drug from the list above. If these treatment options have been exhausted, promethazine may be an alternative; seek expert advice from an acute pain service or anaesthetist.