Nausea

Nausea can be described as a sensation of unease and discomfort in the upper stomach combined with an involuntary urge to vomit. ^{[1] [2] [3]} It often, but not always, precedes vomiting. This effect usually occurs at the onset of the experience and dissipates as the peak takes its toll.

In the context of substance usage, nausea and vomiting can occur as a result of stomach irritation through the consumption of materials which it is not used to digesting. These materials can include things such as chemical powders or plant matter. Alternatively, nausea may occur as a direct pharmacological result of how the particular substance affects the brain. If this is the case, the nausea is therefore inseparable from the experience itself and will likely occur to varying extents regardless of the route of administration.

Nausea is often accompanied by other coinciding effects such as stomach bloating, stomach cramps, and dizziness. It is most commonly induced under the influence of heavy dosages of a wide variety of compounds, such as psychedelics, opioids, GABAergics, deliriants, dissociatives, and stimulants.

Vomiting, also known as purging, puking and throwing up, among other terms, is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. This effect typically occurs during the peak of a substance's effects. It can often greatly relieve the person's physical side effects once it is over. For example, under the influence of many hallucinogenic compounds, it is common for a person to feel that their trip has become significantly more enjoyable after the act of vomiting due to their uncomfortable stomach symptoms suddenly subsiding as a result.

It is worth noting that a person should not brush their teeth immediately after vomiting. This is because the corrosiveness of stomach acid combined with the abrasiveness of brushing can cause permanent damage to a person's teeth when repeated over time. Instead, a person should wash their mouth out with water, mouthwash, a water flosser, or a mixture of baking soda and water (to neutralise the acidity).