Evidence-based harm reduction information sourced from DanceSafe, TripSit, SAMHSA, and other recognised public health organisations. If you are experiencing a medical emergency, call your local emergency services immediately.
USA: 911 (emergency) | SAMHSA: 1-800-662-4357 | Never Use Alone: 1-800-484-3731
UK: 999 (emergency) | FRANK: 0300 123 6600
EU: 112 (emergency) | Local poison control centres
Always begin with the smallest possible dose to assess individual tolerance. Potency varies significantly between sources and batches.
Use reagent test kits and fentanyl test strips. Counterfeit pills containing fentanyl look identical to real pharmaceuticals.
Have a trusted person present or call the Never Use Alone hotline (1-800-484-3731, US) before using substances with overdose risk.
Naloxone (Narcan) reverses opioid overdose within minutes. Available at most pharmacies without prescription in many US states and countries.
Combining depressants (opioids + benzos + alcohol) multiplies overdose risk dramatically. Check TripSit combination chart before mixing any substances.
Mental state (set) and physical environment (setting) heavily influence experience, especially with psychedelics. Choose safe, comfortable settings with trusted company.
Evidence-based safety information for the most commonly used substances. Sources: DanceSafe, TripSit, EMCDDA, NIH.
Overdose risk: Very high. Opioids suppress breathing — overdose can be fatal within minutes. Never use alone. Test for fentanyl with test strips before every use — fentanyl is present in counterfeit pills and even heroin supplies globally.
Overdose signs: Unresponsive, slow/stopped breathing, blue lips or fingertips (cyanosis), pinpoint pupils, gurgling sounds.
What to do: Call emergency services immediately. Administer naloxone (Narcan/Evzio) intranasally or by injection. Perform rescue breathing. Do not leave the person alone. Repeat naloxone dose after 2-3 minutes if no response. Fentanyl may require multiple doses.
Tolerance awareness: Tolerance drops dramatically after even 2-3 days of abstinence. Previous doses can be lethal after a break. Always re-dose conservatively after any period of abstinence.
Resources: DanceSafe — Opioids | TripSit — Heroin
MDMA: Test with Marquis (purple/black = MDMA), Mecke, and Froehde reagent kits. Use fentanyl test strips — fentanyl-laced "ecstasy" has been documented. Dose: max 75-100mg, wait 60-90 min before redosing. Stay hydrated (sip water ~500ml/hour if dancing) but do not overhydrate. Take regular breaks from physical activity to prevent hyperthermia.
Cocaine: Test with Scott reagent (positive = blue). High risk of cardiac events, particularly with physical exertion or pre-existing heart conditions. Never combine with alcohol (produces cocaethylene — more toxic and longer-lasting). Avoid mixing with stimulants.
Methamphetamine: High neurotoxicity with heavy use. Psychosis risk. Avoid sleep deprivation. Test with Marquis (orange/brown). Never combine with MAOIs — potentially fatal.
Resources: DanceSafe — MDMA | TripSit — MDMA
Edibles: Onset can take 30-120 minutes — do NOT redose early. Many cannabis ER visits result from users assuming the edible "didn't work" and doubling the dose, then experiencing overwhelming effects when both doses activate simultaneously.
Concentrates: Dabs and concentrates can contain 60-90% THC compared to 15-25% in flower. Dose very conservatively if transitioning from flower.
Mental health: Cannabis can trigger or exacerbate anxiety, paranoia, and in predisposed individuals, psychotic episodes. Avoid high-THC products if you have a personal or family history of psychosis.
Resources: TripSit — Cannabis
Withdrawal risk: Physical dependence develops within days of daily use. Benzo withdrawal (unlike most drug withdrawals) can be life-threatening, causing seizures. Never abruptly stop daily benzodiazepine use — taper under medical supervision.
Fatal combinations: Any combination with opioids, alcohol, or other CNS depressants dramatically increases overdose risk.
Designer benzodiazepines: Research chemicals like flualprazolam, clonazolam, and bromazolam are significantly more potent and longer-lasting than pharmaceutical equivalents. No antidote equivalent to naloxone exists for benzodiazepine overdose alone. Flumazenil can reverse but has risks including seizure induction in dependent users.
Resources: TripSit — Diazepam
Acute risk: Classic psychedelics (LSD, psilocybin, mescaline) have no known lethal dose in humans and do not cause respiratory depression. The primary risk is behavioural — acting on distorted perceptions in unsafe environments.
Set and setting: Psychological state and physical environment profoundly affect the experience. Have a sober trip sitter present for high doses or new experiences.
HPPD: Rare but possible persistent visual disturbances (Hallucinogen Persisting Perception Disorder). Risk increases with frequency of use and mixing with other substances.
Dangerous combinations: Serotonin syndrome is possible when combining psychedelics with SSRIs, MAOIs, or lithium. Never combine psychedelics with MAOIs unless using ayahuasca-type combinations with expert guidance.
Testing: Use Ehrlich reagent (purple = indole alkaloids, confirms LSD/psilocybin class). Does not distinguish between LSD and dangerous 25x-NBOMe compounds — add Hofmann reagent for better differentiation.
Resources: DanceSafe — LSD | TripSit — LSD | MAPS.org — Research
Bladder damage: Frequent ketamine use causes severe, potentially irreversible bladder damage (ketamine cystopathy). Symptoms include urinary pain, reduced capacity, and in severe cases, the need for surgical removal. Any urinary symptoms should prompt immediate cessation.
Respiratory depression: At very high doses, dissociatives can cause respiratory depression. K-holes (high-dose dissociation) require a safe environment with a sober presence.
DXM: Available in cough medicines — often contains other active ingredients (antihistamines, decongestants) that are dangerous at recreational doses. Use only products containing DXM as the sole active ingredient.
Resources: TripSit — Ketamine
Fentanyl and its analogues are present in the counterfeit drug supply globally. A dose smaller than a grain of salt can be lethal. Fentanyl test strips (FTS) can detect fentanyl in any substance — pills, powders, solutions.
Note: Strips cannot detect all fentanyl analogues and don't measure concentration. A negative result reduces but does not eliminate risk.
Sources: DanceSafe test supplies | Many local harm reduction organisations distribute strips for free