2C-B

2C-B is a synthetic phenethylamine psychedelic with both hallucinogenic and empathogenic properties. Known for visual intensity and euphoria with a clear headspace. Dose-sensitive: small variations dramatically alter the experience. Unpredictable potency and frequent adulteration make it high-risk. Increasingly prevalent in club and chemsex scenes.

How It Works

Partial agonist at serotonin 5-HT2A and 5-HT2C receptors, mediating psychedelic and hallucinogenic effects. May also interact with dopamine receptors (D2, D3) contributing to empathogenic properties. Acts as a releasing agent for serotonin and dopamine.

Legal Status

Controlled in most countries. Classified as a Schedule I substance in the US and similarly restricted internationally. Illegal for all non-research purposes.

Dosage Guide (Oral)

Note: Dose-sensitive: 5mg difference between light and intense experiences. Poorly dosed or adulterated substances are extremely common. No reliable street doses exist. Insufflation typically requires 30-50% less material but causes severe nasal irritation. Purity and potency vary dramatically between batches.

Organ System Impacts

cardiovascular — Moderate

Increases heart rate, blood pressure, and cardiac workload. Risk of arrhythmias, palpitations, and in rare cases myocardial infarction, especially in susceptible individuals or at high doses.

neurological — Moderate

Potent serotonergic activity produces hallucinations, dissociation, and altered cognition. Hallucinogenic effects can trigger latent psychotic disorders. Seizure risk in susceptible individuals at high doses.

ocular — Low

Pupil dilation (mydriasis), visual distortions, and enhanced color perception. Possible photophobia. No permanent ocular damage reported, but impaired vision during acute effects.

dermatological — Low

Profuse sweating common, especially in club/dance settings. Hyperthermia risk in hot environments. Possible rash from adulterated substances.

respiratory — Low

No direct respiratory toxicity. Mild tachypnea possible from sympathomimetic effects. Hyperthermia may increase respiratory rate.

hepatic — Low

Minimal hepatic toxicity reported. Metabolism primarily via monoamine oxidase and other liver enzymes. No significant liver damage in acute or chronic use documented.

hematological — Low

No direct hematological effects. Possible dehydration in prolonged use in hot environments affecting blood volume and viscosity.

renal — Low

Sympathomimetic effects may cause hypertension affecting renal perfusion. Dehydration and SIADH-like effects possible. Risk of rhabdomyolysis and acute kidney injury if hyperthermia occurs.

gastrointestinal — Low

Nausea and vomiting common, particularly with oral route and higher doses. Possible stomach cramping and diarrhea. Appetite suppression during acute effects.

musculoskeletal — Low

Jaw clenching and teeth grinding (bruxism) common. Muscle tension and rigidity possible at higher doses. Risk of rhabdomyolysis with hyperthermia in dance/exertion settings.

Effects

Desired Effects

• Euphoria
• Intense visuals
• Emotional openness
• Sensory enhancement
• Increased empathy
• Laughter
• Music enhancement
• Connection with others

Negative Effects

• Anxiety
• Paranoia
• Nausea and vomiting
• Jaw clenching/tension
• Muscle tension
• Rapid heartbeat
• Restlessness
• Difficulty sleeping

Rare but Serious

• Severe anxiety or panic attack
• Serotonin syndrome
• Seizures
• Acute psychosis
• Cardiac arrhythmias
• Hypertensive crisis

Drug Interactions

Detection Times

2C-B is not detected on standard drug panels. Specialized mass spectrometry testing is required.

Urine

Requires GC-MS or LC-MS/MS. May cross-react on amphetamine assays. Detection window: up to 3 days.

Blood

Short blood detection window. Detection window: up to 1 days.

Hair

Hair testing is theoretically possible but rarely done. Detection window: up to 90 days.

Harm Reduction Tips

• Never use with MAOI antidepressants or certain other antidepressants (SSRIs, tramadol) due to severe serotonin syndrome risk.

• Never combine with stimulants (cocaine, amphetamines, MDMA) due to life-threatening cardiovascular effects.

• Test substance with reagent kits (Marquis, Mecke, Mandelin, Froehde) before consumption. Be aware that 2C-B is frequently mislabeled or adulterated with PMA, NBOMe compounds, or other dangerous substances.

• Start with low doses (10-15 mg oral) to assess individual sensitivity and substance purity. Small dose variations produce dramatically different intensities.

• Stay hydrated and maintain adequate electrolyte balance, especially in hot/dance environments. Drink 250-500mL water per hour in exertion settings, but avoid excessive water intake.

• Monitor body temperature and take breaks from dancing/exertion. Use cool compresses if overheating occurs. Hyperthermia is the primary medical emergency.

• Avoid insufflation whenever possible due to nasal damage risk and unpredictable potency. If snorting, use saline nasal drops pre/post and inspect nasal passages weekly for damage.

• Use in safe, controlled environments with trusted people. Avoid driving or operating machinery. Have a sober trip sitter if possible, especially on higher doses.

• If experiencing severe chest pain, shortness of breath, or uncontrolled rapid heartbeat, seek immediate medical attention.

• Avoid use if you have personal or family history of psychosis, heart disease, or uncontrolled hypertension.

• Practice responsible sexual behavior if using in chemsex contexts. Consent impairment is possible at higher doses.

Withdrawal Symptoms

Severity: Low

Not applicable — 2C-B does not produce dependence.

Psychological

• No significant withdrawal syndrome

Emergency Information

Call 911 If:

• Chest pain or cardiac symptoms
• Severe uncontrolled hypertension
• Hyperthermia above 39°C (102°F)
• Severe confusion or uncontrollable behavior
• Muscle rigidity or severe muscle contractions
• Loss of consciousness or seizures
• Severe respiratory distress
• Any signs of serotonin syndrome

Warning Signs

• Severe chest pain or pressure
• Uncontrollable rapid or irregular heartbeat
• Severe hypertension (headache, dizziness, nosebleeds)
• Uncontrollable high fever (>39°C/102°F)
• Severe agitation, confusion, or hallucinations
• Rigid muscles or uncontrollable muscle contractions
• Loss of consciousness
• Seizures
• Severe breathing difficulty

What To Do

1. Immediately move to a cool, well-ventilated area and lie down with feet elevated.
2. Cool the body with cold compresses, ice packs, or immersion in cool (not ice) water if hyperthermia.
3. Monitor vital signs and consciousness level.
4. Sip water slowly if conscious and no vomiting.
5. If seizure occurs, protect from injury and position on side.
6. Keep person calm and reassured; provide supportive care.
7. If symptoms persist or worsen, contact emergency services.