Several pharmacological agents have disgusting tastes that are perceived strongly in the back of the mouth and may trigger nausea and vomiting (NV), resulting in poor adherence to medication schedules and negative impacts on clinical outcomes. Pleasant stimuli and cold temperature lessen the disgusting stimuli, lowering NV through different mechanisms. A pleasant stimulus can mask an unpleasant one, presumably through lateral inhibitory connections in the local neuronal circuit. Similarly, temperature deeply influences taste perception because the response to bitter as well as to salty and sour has been found to assume a reversed U-shaped form, being reduced by cooling to 18°C and enhanced by warming to 30–37°C. This Review describes the mechanisms by which pleasant and cold stimuli may mask emetogenic disgusting stimuli and identifies the potential clinical applications of cooling for inhibiting objectionable drug-related gustatory reactions. © 2015 Wiley Periodicals, Inc.
Disturbing smells and tastes directly activate the vomiting center after being integrated at the cortical level. Pleasant stimuli and cold temperature lessen the effects of the disgusting stimuli, dampening nausea and vomiting reflexes.