Appetite suppression

Appetite suppression is a reduction in the desire to eat that arises during intoxication rather than from illness or caloric need.

As a drug effect it is acute and dose-proportional, easing as the substance wears off, which sets it apart from clinically significant eating disturbances. It ranges from mild indifference to food to a near-complete absence of hunger.

Appetite suppression is among the most commonly reported somatic effects across psychoactive substances. It is most commonly induced at moderate to high doses under stimulants such as amphetamine, MDMA, and modafinil, and under psychedelics such as LSD, psilocybin mushrooms, and DMT. It also appears under opioids such as heroin, fentanyl, and codeine, and under dissociatives such as dextromethorphan.

Appetite suppression is felt as a quiet withdrawal of hunger: the usual cues — the pull toward food, the awareness of an empty stomach — recede or disappear entirely. Meals feel optional rather than necessary, and the sight or smell of food may provoke indifference or mild aversion rather than appetite.

It is largely passive; most people notice it only when a mealtime arrives and no desire to eat follows. At higher doses, particularly under stimulants, even the thought of food can feel faintly unwelcome.

Appetite suppression arises through different pathways depending on the drug class:

• Stimulants — elevate dopamine and norepinephrine, directly suppressing hunger signaling in proportion to dose.
• Psychedelics — act on serotonin receptors involved in appetite regulation; a broader disruption of ordinary interoceptive awareness likely contributes.
• Opioids — act on opioid receptors in the hypothalamus and gut, blunting normal hunger signaling.
• Dissociatives — block NMDA receptors; appetite suppression appears as part of a wider attenuation of bodily awareness.

How much each pathway contributes in a given case is not fully understood.

Who experiences it, and how strongly, varies widely. Higher doses reliably deepen it, and sustained use — particularly of stimulants — can make it pronounced enough to affect nutrition over time.

Individual metabolism and baseline hunger state both matter; someone who has not eaten for hours will notice it more readily than one who has just eaten. Expectation plays little role: unlike mood effects, appetite suppression is not readily talked into or out of existence. A relaxed set and a substance taken after a meal tend to reduce how noticeably it registers.