Questions About Cancer? 1-800-4-CANCER

Nausea and Vomiting (PDQ®)

Health Professional Version

Anticipatory Nausea and Vomiting (Emesis)


The prevalence of anticipatory nausea and vomiting (emesis) (ANV) has varied, owing to changing definitions and assessment methods.[1] However, anticipatory nausea appears to occur in approximately 29% of patients receiving chemotherapy (about one of three patients), while anticipatory vomiting appears to occur in 11% of patients (about one of ten patients).[2] With the introduction of new pharmacologic agents (5-hydroxytryptamine-3 or 5-HT3 receptor antagonists), it was anticipated that the prevalence of ANV might decline; however, studies have shown mixed results. One study found a lower incidence of ANV,[3] and three studies found comparable incidence rates.[2,4,5] It appears that the 5-HT3 agents reduce postchemotherapy vomiting but not postchemotherapy nausea,[2,5] and the resulting impact on ANV is unclear.

Classical Conditioning

Although other theoretical mechanisms have been proposed,[6] ANV appears to be best explained by classical conditioning (also known as Pavlovian or respondent conditioning).[7] In classical conditioning, a previously neutral stimulus (e.g., smells of the chemotherapy environment) elicits a conditioned response (e.g., ANV) after a number of prior pairings or learning trials. In cancer chemotherapy, the first few chemotherapy infusions are the learning trials. The chemotherapy drugs are the unconditioned stimuli that elicit postchemotherapy nausea and vomiting (N&V) (in some patients). The drugs are paired with a variety of other neutral, environmental stimuli (e.g., smells of the setting, oncology nurse, chemotherapy room). These previously neutral stimuli then become conditioned stimuli and elicit ANV in future chemotherapy cycles. ANV is not an indication of psychopathology but is rather a learned response that, in other life situations (e.g., food poisoning), results in adaptive avoidance.

A variety of correlational studies provide empirical support for classical conditioning. For example, the prevalence of ANV prior to any chemotherapy is very rare, and few patients ever experience ANV without prior postchemotherapy nausea.[8] Also, most studies have found (1) a higher probability of ANV with increasing numbers of chemotherapy infusions, and (2) the intensity of ANV increasing as patients get closer to the actual time of their infusion.[9] In one experimental study, it was shown that a novel beverage could become a conditioned stimulus to nausea when paired with several chemotherapy treatments.[10]

Variables Correlated with ANV

Many variables have been investigated as potential factors that correlate with the incidence of ANV in hopes of developing a list of risk factors. There is currently no agreement on which factors predict ANV. A patient with fewer than three of the first eight characteristics listed below, however, is unlikely to develop ANV, and screening following the first chemotherapy infusion could identify those patients at increased risk.[11]

Variables Found to Correlate With ANV

  1. Age younger than 50 years.
  2. N&V after last chemotherapy session.
  3. Posttreatment nausea described as moderate, severe, or intolerable.
  4. Posttreatment vomiting described as moderate, severe, or intolerable.
  5. Feeling warm or hot all over after last chemotherapy session.
  6. Susceptibility to motion sickness.
  7. Sweating after last chemotherapy session.
  8. Generalized weakness after last chemotherapy session.
  9. Female gender.
  10. High-state anxiety (anxiety reactive to specific situations).[12,13]
  11. Greater reactivity of the autonomic nervous system and slower reaction time.[14]
  12. Patient expectations of chemotherapy-related nausea before beginning treatment.[15,16]
  13. Percentage of infusions of chemotherapy followed by nausea.[17]
  14. Postchemotherapy dizziness.
  15. Lightheadedness.
  16. Longer latency of onset of posttreatment N&V.[18]
  17. Emetogenic potential of various chemotherapeutic agents. Patients receiving drugs with a moderate to severe potential for posttreatment N&V are more likely to develop ANV.[12]
  18. Morning sickness during pregnancy.

Treatment of ANV

Antiemetic drugs do not seem to control ANV once it has developed;[2] however, a variety of behavioral interventions have been investigated.[19] These include the following:

  • Progressive muscle relaxation with guided imagery.[20]
  • Hypnosis.[21]
  • Systematic desensitization.[22]
  • Electromyography and thermal biofeedback.[23]
  • Distraction via the use of video games.[24,25]

Progressive muscle relaxation with guided imagery, hypnosis, and systematic desensitization has been studied the most and is the recommended treatment. Referral to a psychologist or other mental health professional with specific training and experience in working with cancer patients is recommended when ANV is identified. The earlier ANV is identified, the more likely treatment will be effective; thus, early screening and referral are essential. However, physicians and nurses underestimate the incidence of chemotherapy-induced nausea and vomiting.[26][Level of evidence: II]


  1. Andrykowski MA: Defining anticipatory nausea and vomiting: differences among cancer chemotherapy patients who report pretreatment nausea. J Behav Med 11 (1): 59-69, 1988. [PUBMED Abstract]
  2. Morrow GR, Roscoe JA, Kirshner JJ, et al.: Anticipatory nausea and vomiting in the era of 5-HT3 antiemetics. Support Care Cancer 6 (3): 244-7, 1998. [PUBMED Abstract]
  3. Aapro MS, Kirchner V, Terrey JP: The incidence of anticipatory nausea and vomiting after repeat cycle chemotherapy: the effect of granisetron. Br J Cancer 69 (5): 957-60, 1994. [PUBMED Abstract]
  4. Fernández-Marcos A, Martín M, Sanchez JJ, et al.: Acute and anticipatory emesis in breast cancer patients. Support Care Cancer 4 (5): 370-7, 1996. [PUBMED Abstract]
  5. Roscoe JA, Morrow GR, Hickok JT, et al.: Nausea and vomiting remain a significant clinical problem: trends over time in controlling chemotherapy-induced nausea and vomiting in 1413 patients treated in community clinical practices. J Pain Symptom Manage 20 (2): 113-21, 2000. [PUBMED Abstract]
  6. Reesal RT, Bajramovic H, Mai F: Anticipatory nausea and vomiting: a form of chemotherapy phobia? Can J Psychiatry 35 (1): 80-2, 1990. [PUBMED Abstract]
  7. Stockhorst U, Klosterhalfen S, Steingruber HJ: Conditioned nausea and further side-effects in cancer chemotherapy: a review. Journal of Psychophysiology 12 (suppl 1): 14-33, 1998.
  8. Morrow GR, Rosenthal SN: Models, mechanisms and management of anticipatory nausea and emesis. Oncology 53 (Suppl 1): 4-7, 1996. [PUBMED Abstract]
  9. Montgomery GH, Bovbjerg DH: The development of anticipatory nausea in patients receiving adjuvant chemotherapy for breast cancer. Physiol Behav 61 (5): 737-41, 1997. [PUBMED Abstract]
  10. Bovbjerg DH, Redd WH, Jacobsen PB, et al.: An experimental analysis of classically conditioned nausea during cancer chemotherapy. Psychosom Med 54 (6): 623-37, 1992 Nov-Dec. [PUBMED Abstract]
  11. Morrow GR, Roscoe JA, Hickok JT: Nausea and vomiting. In: Holland JC, Breitbart W, Jacobsen PB, et al., eds.: Psycho-oncology. New York, NY: Oxford University Press, 1998, pp 476-484.
  12. Andrykowski MA, Redd WH, Hatfield AK: Development of anticipatory nausea: a prospective analysis. J Consult Clin Psychol 53 (4): 447-54, 1985. [PUBMED Abstract]
  13. Roscoe JA, Morrow GR, Hickok JT, et al.: Biobehavioral factors in chemotherapy-induced nausea and vomiting. J Natl Compr Canc Netw 2 (5): 501-8, 2004. [PUBMED Abstract]
  14. Kvale G, Psychol C, Hugdahl K: Cardiovascular conditioning and anticipatory nausea and vomiting in cancer patients. Behav Med 20 (2): 78-83, 1994 Summer. [PUBMED Abstract]
  15. Montgomery GH, Tomoyasu N, Bovbjerg DH, et al.: Patients' pretreatment expectations of chemotherapy-related nausea are an independent predictor of anticipatory nausea. Ann Behav Med 20 (2): 104-9, 1998 Spring. [PUBMED Abstract]
  16. Shelke AR, Roscoe JA, Morrow GR, et al.: Effect of a nausea expectancy manipulation on chemotherapy-induced nausea: a university of Rochester cancer center community clinical oncology program study. J Pain Symptom Manage 35 (4): 381-7, 2008. [PUBMED Abstract]
  17. Tomoyasu N, Bovbjerg DH, Jacobsen PB: Conditioned reactions to cancer chemotherapy: percent reinforcement predicts anticipatory nausea. Physiol Behav 59 (2): 273-6, 1996. [PUBMED Abstract]
  18. Chin SB, Kucuk O, Peterson R, et al.: Variables contributing to anticipatory nausea and vomiting in cancer chemotherapy. Am J Clin Oncol 15 (3): 262-7, 1992. [PUBMED Abstract]
  19. Carey MP, Burish TG: Etiology and treatment of the psychological side effects associated with cancer chemotherapy: a critical review and discussion. Psychol Bull 104 (3): 307-25, 1988. [PUBMED Abstract]
  20. Lyles JN, Burish TG, Krozely MG, et al.: Efficacy of relaxation training and guided imagery in reducing the aversiveness of cancer chemotherapy. J Consult Clin Psychol 50 (4): 509-24, 1982. [PUBMED Abstract]
  21. Redd WH, Andresen GV, Minagawa RY: Hypnotic control of anticipatory emesis in patients receiving cancer chemotherapy. J Consult Clin Psychol 50 (1): 14-9, 1982. [PUBMED Abstract]
  22. Morrow GR, Morrell C: Behavioral treatment for the anticipatory nausea and vomiting induced by cancer chemotherapy. N Engl J Med 307 (24): 1476-80, 1982. [PUBMED Abstract]
  23. Burish TG, Shartner CD, Lyles JN: Effectiveness of multiple muscle-site EMG biofeedback and relaxation training in reducing the aversiveness of cancer chemotherapy. Biofeedback Self Regul 6 (4): 523-35, 1981. [PUBMED Abstract]
  24. Kolko DJ, Rickard-Figueroa JL: Effects of video games on the adverse corollaries of chemotherapy in pediatric oncology patients: a single-case analysis. J Consult Clin Psychol 53 (2): 223-8, 1985. [PUBMED Abstract]
  25. Vasterling J, Jenkins RA, Tope DM, et al.: Cognitive distraction and relaxation training for the control of side effects due to cancer chemotherapy. J Behav Med 16 (1): 65-80, 1993. [PUBMED Abstract]
  26. Grunberg SM, Deuson RR, Mavros P, et al.: Incidence of chemotherapy-induced nausea and emesis after modern antiemetics. Cancer 100 (10): 2261-8, 2004. [PUBMED Abstract]
  • Updated: March 12, 2015