2C-I Effects

A distinct decrease in hunger and desire to eat, ranging from reduced interest in food to complete disinterest or even physical revulsion at the thought of eating. This effect can persist for many hours beyond the primary experience.

Bodily control enhancement is the subjective feeling of improved physical precision, coordination, and dexterity — a sense of heightened mastery over one's own body that can make movements feel fluid, deliberate, and effortless.

A diffuse, heavy physical discomfort involving tension, pressure, and malaise in the torso and limbs, commonly reported with tryptamines and phenethylamines.

A state of insufficient bodily hydration manifesting as persistent thirst, dry mouth, and physical discomfort, often caused by increased sweating, urination, or simply forgetting to drink water during substance use.

Increased urinary frequency beyond normal patterns, caused by diuretic effects or bladder irritation from substances like alcohol, caffeine, and ketamine.

A noticeable acceleration of heartbeat that can range from a subtle awareness of one's pulse to a forceful, rapid pounding felt throughout the chest, neck, and temples. This effect is among the most commonly reported physiological responses to psychoactive substances and often accompanies stimulation, anxiety, or physical exertion during intoxication.

A marked enhancement of sexual desire, arousal, and sensitivity to erotic stimuli that can range from a gentle heightening of romantic interest to an overwhelming, all-consuming preoccupation with sexual thoughts and physical intimacy. This effect often co-occurs with tactile enhancement and empathy, creating a distinctly sensual state of consciousness.

Muscle cramps are sudden, involuntary, and often painful contractions of muscles that occur as a side effect of certain psychoactive substances, particularly stimulating psychedelics and stimulants.

An uncomfortable sensation of queasiness and stomach discomfort that may or may not lead to vomiting, often occurring during the onset phase of many substances.

An intensely pleasurable bodily sensation that can manifest as waves of warmth, tingling electricity, or a full-body orgasmic glow radiating outward from the core. This effect is often described as one of the most rewarding physical sensations available through psychoactive substances and is a primary driver of the recreational appeal of many substance classes.

A visible enlargement of the pupil diameter (mydriasis) that can range from subtle widening to dramatic saucer-like expansion where the dark pupil dominates the iris. This effect is one of the most recognizable signs of psychedelic and stimulant intoxication and directly contributes to light sensitivity, enhanced color perception, and the characteristic "wide-eyed" appearance.

Stamina enhancement is an increase in one's ability to sustain physical and mental exertion over extended periods without succumbing to fatigue, achieved through substances that modulate energy metabolism, pain perception, or central fatigue signaling.

A state of heightened physical and mental energy characterized by increased wakefulness, elevated motivation, and a subjective sense of vigor that pervades both body and mind. Users often report feeling electrically alive, with a buzzing readiness to move, talk, and engage that can range from a pleasant caffeine-like lift to an overwhelming, jittery compulsion to act.

Impaired thermoregulation causing unpredictable fluctuations between feeling hot and cold, with risk of hyperthermia or hypothermia.

The sense of touch becomes dramatically heightened, making physical contact feel intensely pleasurable and detailed. Textures and skin contact produce amplified richness.

An intensification of the brightness, vividness, and saturation of colors in the external environment, making the world appear dramatically more colorful. Reds seem redder, greens seem greener, and all hues appear richer and more distinct than during ordinary perception.

The visual experience of colors on objects and surfaces cycling through continuous, fluid transformations, shifting from one hue to another in smooth, seamless loops. A green surface might flow through blue, purple, red, and back to green in a mesmerizing animated sequence.

The visual experience of perceiving stationary objects, textures, and surfaces as appearing to flow, breathe, melt, or shift in position. Drifting is one of the most fundamental and commonly reported visual distortions under the influence of psychedelic substances, serving as the perceptual foundation upon which many other visual effects are built. It manifests as a fluid, organic sense of motion embedded in otherwise static visual fields.

A visual distortion in which the environment and objects within it appear fragmented into geometric, cube-like facets, as if reality has been refracted through a crystalline prism. The effect gives surfaces and three-dimensional space a distinctly angular, Cubist art-like quality reminiscent of Picasso or Braque paintings, where multiple perspectives of the same object are perceived simultaneously.

A visual effect in which existing textures and surfaces — carpets, clouds, foliage, walls — spontaneously reorganize into intricate geometric patterns that are clearly composed of the original material rather than being overlaid onto it.

A visual hallucination that manifests within the external environment as though it were physically real, ranging from subtle distortions of existing objects to fully autonomous, detailed scenes and entities that appear indistinguishable from reality.

The experience of perceiving complex, ever-shifting geometric patterns superimposed over the visual field or visible behind closed eyelids. Geometry is widely considered the hallmark visual effect of psychedelic substances, ranging from simple lattice patterns and honeycombs at low doses to infinitely complex, self-transforming fractal structures at high doses that can feel profoundly meaningful and awe-inspiring.

Vivid, detailed visual experiences perceived within an imagined mental landscape that can only be seen with closed eyes, ranging from fleeting imagery and abstract scenes to fully immersive, dream-like environments with autonomous narratives and entities.

An increased ability and tendency to perceive meaningful patterns, faces, and images within ambiguous or random visual stimuli such as textures, clouds, and surfaces.

A hallucinatory phenomenon in which the observer's visual perspective shifts from the normal first-person viewpoint to alternative vantage points — including third-person (seeing oneself from outside), bird's-eye, or omniscient perspectives — during both internal and external hallucinations.

The visual field fractures into distinct, cleanly cut sections that slowly drift apart from their original positions before resetting, as if reality has been sliced by an invisible blade into geometric pieces that briefly separate and rearrange.

The perceived environment in which hallucinatory experiences take place, ranging from recognizable locations drawn from memory to entirely novel alien landscapes, ancient civilizations, cosmic vistas, and impossible architectural spaces.

Textures appear to mirror and tessellate across surfaces in intricate, self-similar symmetrical patterns that maintain detail at every scale. Most prominent in peripheral vision on rough surfaces.

Moving objects leave visible trails of varying length and opacity behind them, similar to long-exposure photography. Trails may match the object color or appear in other hues.

Objects and scenery undergo perceived visual metamorphosis, smoothly shapeshifting into other recognizable forms over seconds. Patterns morph into faces, animals, and imagery.

Vision becomes sharper and more defined than normal, as though a slightly blurry lens has been brought into perfect focus. Edges appear crisp and fine details become vivid.

A perceived improvement in one's ability to logically deconstruct concepts, recognize patterns, and reach novel conclusions, often accompanied by deep states of contemplation and an abundance of insightful ideas.

Intense feelings of apprehension, worry, and dread that can range from a subtle background unease to overwhelming panic attacks with a sense of impending doom, often amplified by the substance's intensification of one's existing mental state.

A blunting or flattening of emotional experience in which feelings become muted, distant, or seemingly absent. The individual may recognize intellectually that they should be feeling something in response to a situation — joy at good news, sadness at a loss, anxiety about a threat — yet the emotional charge simply is not there, as though an invisible pane of glass separates them from their own feelings.

A heightened capacity to become fully absorbed and engrossed in external media such as music, films, video games, and art, with an amplified suspension of disbelief and a deepened emotional connection to the content being experienced.

A dose-dependent inhibition of one's ability to access and utilize short-term and long-term memory, ranging from mild forgetfulness to a profound inability to recall personal identity, biographical information, or the context of the current experience.

A feeling of increased fascination, awe, and childlike wonder attributed to everyday concepts, objects, and experiences, as if perceiving the world for the first time.

Irrational suspicion and belief that others are watching, plotting against, or intending harm toward oneself, ranging from mild unease to overwhelming terror.

Subjective perception of time becomes dramatically altered — minutes may feel like hours, or hours pass in moments. Can manifest as either dilation or compression.

An increased ability to stay awake and alert without the desire to sleep. Distinct from stimulation in that it does not elevate energy above a naturally rested baseline.

Scenarios and plots are the narrative structures that emerge within hallucinatory states — coherent or surreal storylines involving autonomous characters, unfolding events, and immersive settings that can feel as real and consequential as waking life.

Stimulation of one sense triggers involuntary experiences in another — seeing sounds as colors, tasting textures, or hearing visual patterns. A blending of sensory channels.

A profound dissolution of the sense of self in which personal identity, memories, and the boundary between self and world completely vanish, leaving only pure undifferentiated awareness.

A profound sense that identity extends beyond the self to encompass other people, nature, or all of existence. Boundaries between self and other dissolve into felt oneness.