Chemotherapy-induced nausea and vomiting
Chemotherapy-induced nausea and vomiting (CINV) is emesis triggered by cytotoxic therapy through serotonin, substance P, and dopamine pathways converging on the brainstem chemoreceptor trigger zone. Risk is stratified by the emetogenic potential of the regimen, and high-risk regimens such as cisplatin or anthracycline-cyclophosphamide combinations are prevented with a four-drug regimen of an NK1 antagonist, a 5-HT3 antagonist, dexamethasone, and olanzapine.
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What this article covers
- Overview
Definition: chemotherapy-induced nausea and vomiting (CINV) is nausea and emesis provoked by cytotoxic or targeted antineoplastic therapy, from direct stimulation of gut and brainstem emetic pathways.
- Epidemiology
Near-universal exposure: most patients receiving systemic chemotherapy carry some CINV risk, and unprophylaxed high-emetogenic-risk regimens produce vomiting in over 90% of patients.
- Risk factors
Regimen emetogenicity: cisplatin, cyclophosphamide above 1,500 mg/m2, carmustine, dacarbazine, mechlorethamine, and streptozocin carry high emetogenic risk; an anthracycline combined with…
- Pathophysiology
Peripheral trigger: cytotoxic drugs injure gastrointestinal mucosa and enterochromaffin cells, which release serotonin; serotonin binds 5-HT3 receptors on vagal afferent nerve terminals and dominates the acute, first-24-hour phase.
- Clinical features
Acute phase: nausea and vomiting beginning within minutes to hours of chemotherapy and typically resolving within 24 hours, driven predominantly by the serotonin/5-HT3 pathway.
- Differential diagnosis
Bowel obstruction or ileus: absent bowel sounds or high-pitched rushes, distention, and air-fluid levels on imaging distinguish it from CINV, rather than a strict temporal link to the infusion.
- Diagnosis
What establishes the diagnosis: CINV is a clinical diagnosis made from the temporal relationship between symptom onset and the chemotherapy infusion in a patient without another identified cause; no single test confirms it.
- Management
First, match prophylaxis to emetogenic risk before cycle 1: high-risk regimens (above 90% vomiting risk unprophylaxed: cisplatin, cyclophosphamide above 1,500 mg/m2, carmustine, dacarbazine…
- Complications
Dehydration and acute kidney injury: from sustained inability to maintain oral intake, worsened by nephrotoxic agents such as cisplatin.
- Prognosis
Acute and delayed CINV: highly controllable with guideline-concordant prophylaxis, unlike the era before 5-HT3 and NK1 antagonists replaced dopamine-antagonist-based regimens as standard.
- Prevention
Match prophylaxis to the emetogenic tier of every new regimen before the first dose, since risk is set by the drugs and doses given, not discovered after a patient vomits.
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Related articles
- Antiemetics
Antiemetics are grouped by the receptor they block along the emetic pathway, and correct use is a matching exercise: identify the trigger (chemotherapy, postoperative, vestibular, gastroparesis, or pregnancy) and select the class built for that pathway, most often a 5-HT3 antagonist, a D2 antagonist, an NK1 antagonist, or an antihistamine/anticholinergic, layered with dexamethasone for chemotherapy-induced disease.
- Alkylating agents
Alkylating agents are cell cycle nonspecific cytotoxic drugs that cross-link DNA strands, triggering apoptosis in dividing cells. They underpin regimens for lymphoma, leukemia, myeloma, and solid tumors, and are dosed by body surface area or fixed dose with mesna, hydration, and antiemetic prophylaxis to limit hemorrhagic cystitis, myelosuppression, and gonadal toxicity.
- Antimetabolites
Antimetabolites are structural analogs of folate, purine, or pyrimidine substrates that block DNA and RNA synthesis in dividing cells. The class includes methotrexate, the fluoropyrimidines, cytidine and purine analogs, and hydroxyurea, and underpins first-line therapy for leukemias, lymphomas, and solid tumors, dosed with leucovorin rescue, folic acid, or pharmacogenomic testing to limit myelosuppression.
- Antitumor antibiotics
Antitumor antibiotics are natural-product cytotoxic drugs, dactinomycin, the anthracyclines, bleomycin, and mitomycin, that damage DNA or RNA directly. Clinicians treat lymphoma, pediatric solid tumors, germ cell tumors, and anal and bladder cancer with these agents as chemotherapy backbones, but each member carries a distinct, cumulative-dose-limited organ toxicity.
- Chemotherapy extravasation
Chemotherapy extravasation is leakage of a vesicant or irritant antineoplastic drug from the vein into surrounding tissue, diagnosed clinically by pain, swelling, and loss of blood return during infusion. First-line treatment is immediate cessation of the infusion, aspiration of residual drug, and an agent-specific antidote: dexrazoxane for anthracyclines or hyaluronidase for vinca alkaloids.
- Neutropenic fever
Neutropenic fever is an oncologic emergency defined as a single oral temperature of 38.3 C or higher, or 38.0 C sustained for 1 hour, with an ANC of 500/microL or lower, most often during the chemotherapy nadir. Management is empiric antipseudomonal beta-lactam therapy within 60 minutes, with vancomycin, antifungal therapy, and growth factors added only for specific indications.