Olfactory enhancement can be described as the experience of smells becoming significantly richer, stronger, and more noticeable than that of everyday sobriety. This experience can either be positive or negative depending on the smell and the person's prior opinion of them. For example, while certain smells such as food or flowers may become a true delight during this experience, other smells such as pollution or body odour may become overpowering in an uncomfortable manner which can potentially trigger nausea and vomiting.
Olfactory enhancement is often accompanied by other coinciding effects such as acuity enhancement, tactile enhancement, and auditory enhancement. It is most commonly induced under the influence of moderate dosages of psychedelic compounds, such as LSD, psilocybin, and mescaline. However, it can also occur to a lesser extent under the influence of certain stimulants and dissociatives such as MDMA or 3-MeO-PCP.