Postoperative Nausea & Vomiting (PONV)
Plan prevention, prompt rescue and discharge treatment together. PONV can delay drinking, mobilization and discharge; persistent vomiting after abdominal reconstruction also warrants assessment for a surgical or metabolic cause. This workflow follows the Fifth Consensus Guidelines, first published online in 2025, with current product-label safety precautions.[1]
See also: Anesthesia, Analgesia, ERAS, Constipation & Ileus, and Corticosteroid pharmacology.
Assess Risk and Reduce Emetic Exposure
The adult Apfel score assigns one point each for female sex, nonsmoking, prior PONV or motion sickness and anticipated postoperative opioids. Historical approximate risks with 0–4 factors are 10%, 20%, 40%, 60% and 80%. The Fifth Consensus groups patients as low risk (0 factors), medium risk (1–2) and high risk (3 or more). The Fifth Consensus identifies urologic and gynecologic surgery, laparoscopic cholecystectomy and bariatric surgery as added PONV risks. Many centers now give multimodal prophylaxis to every general-anesthesia patient; risk assessment still informs prevention.[1]
| Adult risk | Prevention approach |
|---|---|
| No Apfel factors | Low Apfel risk; assess the operation and consequences of vomiting. The Fifth Consensus proposes two prophylactic interventions for adults at any PONV risk, while a correctly implemented risk-adapted pathway remains valid.[1] |
| One or two factors | Use two preventive interventions, usually antiemetics from different classes plus appropriate baseline-risk reduction. |
| Three or four factors, or severe prior PONV | Multimodal prophylaxis with additional agents as appropriate and stronger baseline-risk mitigation. No single fixed triple regimen suits every patient. |
Use opioid-sparing analgesia, adequate hydration, propofol-based TIVA or regional or local techniques when suitable, and minimize volatile anesthetic or nitrous-oxide exposure. Propofol TIVA lowers PONV risk to roughly the level of volatile anesthesia plus a 5-HT₃ antagonist or droperidol, and it also adds to other antiemetics. Nitrous oxide as maintenance increases PONV. IV acetaminophen given before pain begins reduces nausea as part of multimodal analgesia. Avoid turning one retrospective model's blood-loss, positioning or laboratory associations into universal treatment thresholds. Adequate hydration does not mean indiscriminate fluid loading in cardiac or renal disease.[1]
Select a Practical Adult Prophylactic Regimen
Dexamethasone plus a 5-HT₃ antagonist is a well-studied combination. Add or substitute another class according to previous response, QT risk, retention or delirium risk and formulary availability. Combination therapy is generally more effective. The large Cochrane network review included 585 trials; evidence for vomiting prevention was stronger than evidence for uncommon serious harms.[1][2]
| Option | Adult workflow example | Important qualification |
|---|---|---|
| Dexamethasone | 4–8 mg IV at induction | Monitor glucose; coordinate with existing glucocorticoid coverage.[1] |
| Ondansetron | 4 mg IV near the end of surgery | Timing differs from dexamethasone. Oral prophylaxis is not dose-equivalent to 4 mg IV.[1] |
| Palonosetron | 0.075 mg IV | Longer acting; avoid routine repeat dosing in PACU.[1] |
| Aprepitant | 40 mg orally before surgery | An NK₁ alternative/addition; review interactions and hormonal-contraception counseling.[1] |
| IV aprepitant, APONVIE | 32 mg over 30 seconds before induction | FDA-labeled adult prophylaxis formulation; do not substitute chemotherapy formulations/doses automatically.[3] |
| Amisulpride, BARHEMSYS | 5 mg IV over 1–2 minutes at induction | Prevention dose differs from the 10-mg treatment dose; QT precautions apply.[4] |
| Haloperidol | 0.5–2 mg IV (1 mg is roughly equivalent to droperidol 0.625 mg) | Off label. Comparable efficacy to 5-HT₃ antagonists in trials, with QT and sedation effects. Often used where droperidol is restricted.[1] |
| Metoclopramide | 10 mg IV | Although 10 mg has shown efficacy, metoclopramide was inferior to dexamethasone and droperidol for prophylaxis through 24 hours; the Fifth Consensus does not recommend it for prophylaxis but notes it may be an alternative when other dopamine antagonists are unavailable.[1] |
| Fosaprepitant | 150 mg IV (off label) | Ranked highest for vomiting prevention within 24 hours in the Cochrane network analysis, with moderate-certainty evidence from direct comparisons with ondansetron but an indirect placebo estimate; the analysis had no adverse-event data for it.[1][2] |
| Promethazine | 6.25 mg IV for rescue (consensus-supported low dose, below the label’s usual adult 12.5–25 mg) | The labeled IV dilution table starts at 12.5 mg; confirm a 6.25-mg preparation plan and apply the tissue-injury precautions below. Sedation and anticholinergic effects remain relevant; with concomitant opioids, the PHENERGAN label calls for an individualized opioid dose reduction of one-quarter to one-half.[1][9] |
| Droperidol | Consensus prophylactic dose 0.625 mg IV near the end of surgery | US boxed warning, patient selection and ECG monitoring requirements remain relevant.[1][5] |
| Transdermal scopolamine | One patch the prior evening; US PONV label removes it 24 hours after surgery | Delayed onset; retention, cognitive and heat-related risks may favor another agent. |
Some consensus-supported uses are off label; use the specific product's administration instructions and patient-specific limits.[1][3][4][5][6]
Safety Checks That Change Selection
- QT and interactions: assess QT-prolonging combinations, potassium and magnesium and cardiac history. BARHEMSYS labeling advises avoiding congenital long-QT syndrome and concurrent droperidol, with ECG monitoring in susceptible patients. Droperidol's US label reserves use for inadequate response or intolerance to other treatments, contraindicates known or suspected QT prolongation, and requires a pretreatment ECG plus monitoring for 2–3 hours afterward.[4][5]
- Ondansetron: avoid congenital long-QT syndrome; concomitant apomorphine is contraindicated. Severe hepatic impairment limits the total daily dose to 8 mg. The labeled oral adult PONV prophylaxis dose is 16 mg one hour before induction.[7]
- Dexamethasone: a studied single perioperative dose has reassuring SSI evidence, but can cause transient hyperglycemia. Required hydrocortisone coverage is not a proven equivalent antiemetic regimen. Coordinate total steroid exposure and consider a non-steroid antiemetic; see Steroids for PADDI and adrenal coverage.[1]
- Scopolamine: can worsen urinary retention and confusion; avoid angle-closure glaucoma. After urogynecologic surgery the patch is associated with failed voiding trials: 45.9% versus 29.4% in one retrospective chart review of 449 women (adjusted OR 1.75, 95% CI 1.08–2.85)[11], while a pooled analysis of four retrospective cohorts (752 patients) found a nonsignificant RR of 2.35 (95% CI 0.61–9.07)[10]. The Fifth Consensus says another antiemetic may be considered after urogynecologic surgery to reduce urinary-retention risk. Its 2025 label adds hyperthermia and decreased-sweating precautions. Avoid excessive heat, and remove the patch and seek assessment if hyperthermia or concerning neuropsychiatric effects occur, or if difficulty urinating develops. Follow its removal instructions, including before MRI.[1][6][10][11]
- Aprepitant: concomitant pimozide is contraindicated because aprepitant can raise pimozide exposure and prolong QT. Review other CYP interactions; monitor INR for two weeks after administration in patients taking warfarin, especially on days 7–10; advise backup nonhormonal contraception for one month.[3]
Severe tissue injury, including gangrene, can occur. FDA prefers deep IM administration. If IV administration is necessary, follow the current diluted-infusion instructions using a large vein, preferably a central catheter; do not use a hand or wrist vein or administer an undiluted IV push. The FDA instructions specify normal-saline dilution, a concentration no greater than 1 mg/mL and infusion over 20–40 minutes.[9] Stop and evaluate infusion-site pain. Promethazine is contraindicated below age two because of respiratory-depression risk.[8][9]
Class Side Effects at a Glance
| Class | Main adverse effects |
|---|---|
| 5-HT₃ antagonists | Headache and constipation; QT prolongation (ondansetron label) |
| Dopamine antagonists (droperidol, haloperidol, amisulpride, metoclopramide) | Sedation, extrapyramidal effects, QT prolongation (dose- and agent-dependent) |
| Dexamethasone | Transient hyperglycemia |
| Antihistamines and promethazine | Sedation, dry mouth, dizziness; anticholinergic urinary retention |
| Scopolamine | Dry mouth, blurred vision, dizziness, urinary retention, confusion |
| NK₁ antagonists | Constipation, fatigue, headache (IV aprepitant label) |
Scopolamine and promethazine warrant caution in patients with impeded urine flow, including bladder-neck obstruction; scopolamine also warrants caution after urogynecologic surgery.[1][6][9][11]
Treat Breakthrough PONV
Check which agents were given, at what time and at what dose. Assess pain, opioids, hydration, hypotension and other causes; after major abdominal surgery, consider ileus, obstruction, leak or infection when symptoms or examination warrant it. A nasogastric tube is a treatment for selected distension or obstruction, not routine PONV rescue.
- Choose a different pharmacologic class after failed prophylaxis. If no prophylaxis was given, ondansetron 4 mg IV is one option.[1]
- Amisulpride 10 mg IV over 1–2 minutes is labeled for adult treatment after no prophylaxis or prophylaxis with another class; apply its QT precautions.[4]
- Immediate repeat dosing of the same class is usually ineffective. After more than six hours, a repeat short-acting 5-HT₃ antagonist or butyrophenone can be considered when alternatives are unavailable, within dose and safety limits.
- Do not routinely repeat long-acting palonosetron, aprepitant or fosaprepitant or dexamethasone in PACU. Scopolamine's delayed onset makes it unsuitable as the sole immediate rescue for active vomiting.[1][4]
IV aprepitant's FDA indication is prophylaxis.[3] Escalate persistent symptoms and reassess the diagnosis rather than repeatedly stacking sedating or QT-prolonging medicines.
Children and Discharge Planning
Use pediatric risk assessment and weight-based dosing, not adult Apfel probabilities. The Fifth Consensus recommends one preventive agent for children without clear risk factors, two for those with 1–2 factors, and at least two plus baseline-risk mitigation for higher risk. Its common-dose examples are ondansetron 0.05–0.1 mg/kg (up to 4 mg) and dexamethasone 0.15 mg/kg (up to 4 mg); the VPOP and POVOC scores replace Apfel, and post-pubertal female sex, anticholinesterase reversal and volatile anesthesia add risk; pediatric anesthesia should determine age-appropriate indications and administration.[1]
Before ambulatory discharge, address continuing nausea, hydration and access to rescue treatment. Consider longer-acting prophylaxis for patients at high risk of postdischarge nausea and vomiting. Give return instructions for persistent inability to drink, severe or distending abdominal pain, fever or other concerning symptoms.
Urologic procedures are associated with higher PONV risk in the cited consensus.[1] In a multicenter study of 2,170 US adults undergoing ambulatory surgery with general anesthesia, 37% reported postdischarge nausea or vomiting through postoperative day 2.[12] Independent predictors included female sex, age under 50 years, prior anesthesia-related nausea or vomiting, PACU opioid use and PACU nausea.[12] Ambulatory GU cases therefore justify a discharge plan.[1] Alvimopan treats selected postoperative ileus risk.
References
1. Gan TJ, Jin Z, Ayad S, et al. Fifth consensus guidelines for the management of postoperative nausea and vomiting: executive summary. Anesth Analg. 2026;143(3):497–513; online November 14, 2025. doi:10.1213/ANE.0000000000007816. Full report; supplementary tables.
2. Weibel S, Rücker G, Eberhart LHJ, et al. Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network meta-analysis. Cochrane Database Syst Rev. 2020;10:CD012859. doi:10.1002/14651858.CD012859.pub2
3. APONVIE (aprepitant) prescribing information. DailyMed.
4. BARHEMSYS (amisulpride) prescribing information. DailyMed.
5. Droperidol injection prescribing information. DailyMed.
6. TRANSDERM SCŌP (scopolamine) prescribing information, including 2025 hyperthermia warning. DailyMed.
7. Ondansetron oral prescribing information. DailyMed.
8. FDA. Updated labeling to reduce severe tissue injury from promethazine injection. December 27, 2023. Safety communication.
9. PHENERGAN injection prescribing information. DailyMed.
10. Lanpher NW, Schnittka EM, Haggag A. Transdermal scopolamine and urinary retention following urogynecologic surgery: a systematic review and meta-analysis. Int Urogynecol J. 2023;34(8):1689-1696. doi:10.1007/s00192-023-05467-8
11. Courtepatte A, Kelly M, Minassian VA. The effect of preoperative scopolamine patch use on postoperative urinary retention in urogynecologic surgeries. Int Urogynecol J. 2023;34(4):861-866. doi:10.1007/s00192-022-05165-x
12. Apfel CC, Philip BK, Cakmakkaya OS, et al. "Who is at risk for postdischarge nausea and vomiting after ambulatory surgery?" Anesthesiology. 2012;117(3):475–486. doi:10.1097/ALN.0b013e318267ef31