25I-NBOH produces 78 documented subjective effects across 6 categories.
Full 25I-NBOH profileWithin twenty minutes, a sharpening of the visual field announces the arrival of the experience. Colors begin to pop with increasing intensity -- reds deepen, greens fluoresce, and blues acquire an electric depth. A mild stimulant energy builds in the chest and limbs, but it carries none of the vasoconstriction-heavy body load that makes its NBOMe counterpart so physically demanding. The body feels energized but not wired, alert but not tense. There is an anticipatory excitement as the visual effects begin to accelerate.
By the one-hour mark, the visual component has blossomed into something spectacular. 25I-NBOH is among the most visually potent compounds in the NBOx series, and at the peak it delivers a torrent of geometric complexity that rivals 25I-NBOMe without the punishing physical cost. Intricate, symmetrical patterns tile across every surface -- elaborate mandalas, crystalline lattices, and spiraling fractals that pulse and shift with mechanical precision. Colors are vivid beyond natural possibility, glowing with an internal luminance that makes the world appear rendered in stained glass. Afterimages trail behind moving objects in prismatic ribbons. The visual field seems to contain more information than the eyes normally process, as though the brain's pattern-recognition systems have been pushed into overdrive.
The headspace is remarkably clear for the level of visual intensity. Thoughts are lucid, organized, and gently accelerated. There is a euphoric brightness to the mood -- a sense of wonder and engagement with the visual spectacle that maintains its novelty throughout the peak. Music is dramatically enhanced, with sounds seeming to generate visual counterparts in real time. Socially, the experience lends itself to animated conversation and shared exploration of the altered perceptual landscape. The body load, while not absent, is manageable: mild jaw tension, a slight elevation in heart rate, and occasional waves of warmth. Compared to 25I-NBOMe, the physical experience is noticeably more comfortable, allowing greater attention to be directed toward the extraordinary visual content.
The peak sustains for two to three hours before gradually subsiding. The geometric overlays thin and eventually fade, leaving behind hours of enhanced color perception and gentle visual shimmer. The stimulant component eases into a calm alertness. Total duration spans six to eight hours. The comedown is smooth and the aftermath is surprisingly clean -- mild fatigue, perhaps, but little of the physical wreckage that the NBOMe compounds can leave in their wake.
Abnormal heartbeat (arrhythmia) is any deviation from the heart's normal rhythm — including beats that are too fast (tachycardia), too slow (bradycardia), or irregularly spaced — and represents one of the more medically significant cardiovascular effects of psychoactive substances.
Appetite suppressionA 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.
Body loadA diffuse, heavy physical discomfort involving tension, pressure, and malaise in the torso and limbs, commonly reported with tryptamines and phenethylamines.
DehydrationA 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.
Difficulty urinatingDifficulty urinating, also known as urinary retention, is the experience of being unable to easily pass urine despite a full bladder, commonly caused by stimulant, opioid, and anticholinergic substances that affect bladder muscle control.
Dry mouthA persistent, uncomfortable reduction in saliva production causing the mouth and throat to feel parched, sticky, and difficult to swallow through, commonly known as cottonmouth.
Frequent urinationIncreased urinary frequency beyond normal patterns, caused by diuretic effects or bladder irritation from substances like alcohol, caffeine, and ketamine.
HeadacheA painful sensation of pressure, throbbing, or aching in the head that can range from a dull background discomfort to a debilitating pounding that dominates awareness. Substance-induced headaches may occur during the acute effects, during the comedown, or as a rebound symptom hours to days after use.
Increased blood pressureIncreased blood pressure (hypertension) is an elevation of arterial pressure above the normal 120/80 mmHg baseline, commonly caused by stimulants, vasoconstrictors, and substances that activate the sympathetic nervous system, posing cardiovascular risks that increase with dose and pre-existing conditions.
Increased bodily temperatureIncreased bodily temperature (hyperthermia) is an elevation of core body temperature above the normal 37C (98.6F) baseline, caused by substances that increase metabolic rate, impair thermoregulation, or promote sustained physical activity, and representing one of the most dangerous physical effects when severe.
Increased heart rateA 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.
Increased libidoA 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.
Laughter fitsSpontaneous, uncontrollable, and often prolonged episodes of intense laughter that erupt without any identifiable cause or genuine feeling of humor, sometimes persisting to the point of tears, aching muscles, and difficulty breathing or speaking.
Mouth numbingMouth numbing is a localized loss of sensation in the tongue, gums, cheeks, and surrounding oral tissues that occurs either from sublingual/buccal drug administration or from substances that possess inherent local anesthetic properties.
Muscle crampMuscle 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.
Muscle tensionPersistent partial contractions or tightening of muscles that produces uncomfortable stiffness, cramping, and low-level aches throughout the body.
NauseaAn uncomfortable sensation of queasiness and stomach discomfort that may or may not lead to vomiting, often occurring during the onset phase of many substances.
Perception of bodily lightnessPerception of bodily lightness is the subjective feeling that one's body has become dramatically lighter — sometimes nearly weightless — producing sensations of buoyancy, effortless movement, and a bouncy, energized physical state.
Physical euphoriaAn 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.
Pupil dilationA 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.
Restless legsRestless legs is an uncomfortable neurological effect characterized by an irresistible compulsion to move the legs (and sometimes other limbs) to relieve unpleasant crawling, aching, or tingling sensations, particularly during periods of rest or inactivity.
SeizureUncontrolled brain electrical activity causing convulsions and loss of consciousness -- a life-threatening medical emergency requiring immediate help.
Serotonin syndromeSerotonin syndrome is a potentially fatal medical emergency caused by excessive serotonergic activity in the central and peripheral nervous systems, typically resulting from combining multiple serotonin-elevating substances, and manifesting as a dangerous triad of neuromuscular hyperactivity, autonomic dysfunction, and altered mental status.
StimulationA 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.
Stomach crampStomach cramps are sharp, intermittent pains in the abdominal region that can occur when psychoactive substances irritate the gastrointestinal lining or alter the normal patterns of smooth muscle contraction in the digestive tract.
Temperature regulation disruptionImpaired thermoregulation causing unpredictable fluctuations between feeling hot and cold, with risk of hyperthermia or hypothermia.
VasoconstrictionA narrowing of blood vessels throughout the body that produces sensations of cold extremities, tingling in the fingers and toes, and a general feeling of circulatory restriction. Users may notice their hands and feet becoming pale, numb, or uncomfortably cold, sometimes accompanied by a sense of tightness in the chest or head.
A visual phenomenon in which a faint, ghostly imprint of a previously viewed image persists in the visual field after the original stimulus has been removed or one has looked away. These lingering visual echoes are significantly more persistent, vivid, and detailed than normal physiological afterimages, often retaining color and form for several seconds or longer and overlaying themselves onto whatever one currently views.
Brightness alterationPerceived increase or decrease in environmental brightness beyond actual illumination levels, common with stimulants and psychedelics (brightening) or sedatives (darkening).
Colour enhancementAn 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.
Colour replacementA visual phenomenon in which the colors of objects or the entire visual field are statically replaced with alternative hues — the green leaves of a tree might appear red, a white wall might turn blue, or the entirety of vision might acquire a single-color tint that persists without cycling.
Colour shiftingThe 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.
Depth perception distortionsAlterations in how the distance of objects within the visual field is perceived, causing layers of scenery to appear exaggerated, rearranged, flattened, or warped in spatial depth.
DiffractionThe experience of seeing rainbow-like spectrums of color and prismatic halos embedded within bright light sources and reflective surfaces, caused by pupil dilation altering how light enters the eye.
DriftingThe 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.
Frame rate suppressionPerception of visual motion as choppy discrete frames rather than smooth continuous flow, resembling low-FPS video, most common with dissociatives.
GeometryThe 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.
Internal hallucinationVivid, 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.
MagnificationA visual distortion in which objects appear larger or closer than they actually are, as though one's visual field has been zoomed in, making distant details seem within arm's reach and nearby objects appear oversized or looming.
Pattern recognition enhancementAn increased ability and tendency to perceive meaningful patterns, faces, and images within ambiguous or random visual stimuli such as textures, clouds, and surfaces.
Perspective distortionsDistortion of perceived depth, distance, and size of real objects, making things appear closer, further, larger, or smaller than they actually are.
Perspective hallucinationA 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.
RecursionThe visual field begins to repeat and nest within itself in a self-similar, fractal-like manner, as if reality is being reflected between infinite mirrors. Sections of scenery duplicate and zoom inward or outward in recursive loops that defy spatial logic.
Scenery slicingThe 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.
Settings, sceneries, and landscapesThe 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.
Symmetrical texture repetitionTextures 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.
TracersMoving 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.
TransformationsObjects and scenery undergo perceived visual metamorphosis, smoothly shapeshifting into other recognizable forms over seconds. Patterns morph into faces, animals, and imagery.
Visual acuity enhancementVision 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 complete or partial inability to form new memories or recall existing ones during and after substance use, ranging from minor gaps in recollection to total blackouts encompassing hours of experience.
Analysis enhancementA 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.
AnxietyIntense 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.
Conceptual thinkingA shift in the nature of thought from verbal, linear sentence structures to intuitive, non-linguistic concepts that are felt and understood rather than spoken by an internal narrator.
ConfusionAn impairment of abstract thinking marked by a persistent inability to grasp or comprehend concepts and situations that would normally be perfectly understandable during sobriety.
Feelings of impending doomFeelings of impending doom is the sudden onset of an overwhelming, visceral certainty that something terrible is about to happen — often one's own death, a medical crisis, or the end of the world — despite the absence of any rational basis for this belief.
Immersion enhancementA 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.
Increased sense of humorA general amplification of one's sensitivity to finding things humorous and amusing, often causing previously unremarkable stimuli to become inexplicably hilarious, with laughter triggered by observations and connections that seem profound or absurd in the altered state.
Memory suppressionA 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.
Novelty enhancementA feeling of increased fascination, awe, and childlike wonder attributed to everyday concepts, objects, and experiences, as if perceiving the world for the first time.
ParanoiaIrrational suspicion and belief that others are watching, plotting against, or intending harm toward oneself, ranging from mild unease to overwhelming terror.
Personal bias suppressionA decrease in the personal, cultural, and cognitive biases through which one normally filters their perception, enabling more objective self-examination and worldview analysis.
Thought accelerationThe experience of thoughts occurring at a dramatically increased rate, as if the mind has been shifted into a higher gear. Ideas, associations, and internal dialogue cascade rapidly, often outpacing the ability to articulate or fully process each one, producing a subjective sense of heightened mental velocity.
Thought decelerationThe experience of thoughts occurring at a markedly reduced pace, as if the mind has been placed into slow motion. Internal dialogue becomes sparse and sluggish, with each idea taking longer to form and process, producing a sense of mental heaviness or cognitive inertia.
Time distortionSubjective perception of time becomes dramatically altered — minutes may feel like hours, or hours pass in moments. Can manifest as either dilation or compression.
WakefulnessAn 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.
Auditory distortion is the experience of sounds becoming warped, pitch-shifted, flanged, or otherwise altered in their perceived qualities without any change to the actual sound source. Familiar sounds may seem alien, stretched in time, or layered with unusual resonances, creating a surreal and sometimes unsettling soundscape that departs significantly from sober auditory perception.
Auditory enhancementAuditory enhancement is a heightened sensitivity and appreciation of sound in which music, voices, and ambient noise become richer, more detailed, and more emotionally resonant. Subtle sonic details that would normally go unnoticed — the texture of a guitar string, the breath between a singer's words, the layered harmonics of a chord — become vivid and captivating.
Auditory hallucinationAuditory hallucination is the perception of sounds that have no external source — hearing music, voices, environmental noises, or abstract sonic phenomena that exist entirely within the mind. These range from faint, ambiguous whispers at the edge of perception to fully formed, complex musical compositions or conversational speech that can feel completely real and externally sourced.
Auditory misinterpretationAuditory misinterpretation is the brief, spontaneous misidentification of real sounds as entirely different sounds — ambient noise interpreted as voices, mechanical hums perceived as music, or random environmental sounds heard as words or familiar patterns.
Dosage independent intensity is the uncommon and poorly understood phenomenon in which a person experiences effects far more intense than their dose would normally produce — such as full ego dissolution from a threshold amount — defying the expected dose-response relationship.
Gustatory hallucinationGustatory hallucinations are phantom taste experiences in which distinct flavors manifest in the mouth without any corresponding food, drink, or chemical stimulus. They range from common metallic or chemical tastes to complex, sometimes entirely alien flavor profiles.
MachinescapesMachinescapes are complex multisensory hallucinations involving the perception of enormous mechanical landscapes built from interlocking gears, pulleys, conveyor belts, and other industrial components, often felt as extensions of or replacements for one's own body.
Scenarios and plotsScenarios 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.
Sensory overloadAn overwhelming flood of sensory information that exceeds the brain's ability to process, creating a chaotic cascade of sights, sounds, and tactile sensations that can temporarily disconnect one from coherent awareness of the external world.
SynaesthesiaStimulation 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.
Existential self-realizationA sudden, visceral realization of the profound significance and improbability of one's own existence as a conscious being within the universe, often accompanied by overwhelming awe and a fundamental shift in perspective about life and reality.
Unity and interconnectednessA 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.
25I-NBOH can produce 27 physical effects including appetite suppression, increased heart rate, vasoconstriction, increased libido, and 23 more.
Yes. 25I-NBOH can produce 22 visual effects including settings, sceneries, and landscapes, pattern recognition enhancement, symmetrical texture repetition, depth perception distortions, and 18 more.
25I-NBOH produces 16 cognitive effects including personal bias suppression, increased sense of humor, immersion enhancement, thought acceleration, and 12 more.