Substance Profiles

Substance-Specific Harm Reduction Information

Risk levels, dangerous combinations, and safer-use guidance for the most commonly encountered substances. Sourced from public health literature.

Opioids (Heroin, Fentanyl, Oxycodone, Morphine)

Overdose Risk: Very High

Opioids carry the highest overdose mortality due to respiratory depression. Tolerance drops rapidly during abstinence — relapse at previous doses is extremely dangerous.

Key risks: Fentanyl contamination is widespread in many regions. Test every batch with fentanyl test strips.

Never combine with: Benzodiazepines, alcohol, GHB, or other opioids without medical supervision.

Resources: National Harm Reduction Coalition

MDMA (Ecstasy / Molly)

Overdose Risk: Moderate

Adulteration with methamphetamine, cathinones, or PMA is common. Test with Marquis and Simon's reagents.

Key risks: Hyperthermia and hyponatremia from over-hydration are leading causes of MDMA-related death.

Never combine with: MAOIs or lithium — can cause fatal serotonin syndrome.

Resources: DanceSafe MDMA Guide

Cocaine & Crack Cocaine

Overdose Risk: High (cardiac)

Significant cardiovascular risk — heart attack or stroke even in young individuals. Risk increases sharply when combined with alcohol (cocaethylene).

Key risks: Fentanyl is increasingly found in cocaine supplies. Test all batches.

Resources: Erowid Cocaine Information

Cannabis (THC/CBD)

Overdose Risk: Low

No confirmed lethal overdose from cannabis alone. Synthetic cannabinoids (Spice, K2) are highly dangerous. Edibles have delayed onset — wait 2 hours before re-dosing.

Resources: TripSit Cannabis Profile

Psychedelics (LSD, Psilocybin, DMT, Mescaline)

Overdose Risk: Low (psychological risk: moderate)

Physiologically non-toxic at typical doses. "LSD" is frequently NBOMe compounds — test with Ehrlich reagent (purple = indole psychedelic).

Resources: MAPS Zendo Project

Benzodiazepines (Xanax, Diazepam, Etizolam)

Overdose Risk: High (combination risk)

Primary danger is combination with opioids or alcohol. Physical dependence develops in 2–4 weeks. Withdrawal can be life-threatening — seek medical supervision.

Resources: Benzo.org.uk

Amphetamines & Methamphetamine

Overdose Risk: High (cardiac / psychiatric)

Elevated heart rate, blood pressure, and body temperature. Stimulant psychosis can develop with sleep deprivation and heavy use.

Resources: SMART Recovery

GHB / GBL

Overdose Risk: Very High

Extremely narrow margin between recreational and unconsciousness doses. Measure with a graduated syringe. Never combine with alcohol.

Resources: TripSit GHB Profile

Dissociatives (Ketamine, PCP, DXM)

Overdose Risk: Moderate

Primary risk is injury from falls. Frequent ketamine use causes bladder damage (ketamine cystopathy).

Resources: DanceSafe Ketamine Information

For overdose steps see overdose response guide. For testing see drug testing guide.