Harm Reduction Guide
Evidence-based information for minimizing health risks associated with substance use. Tested protocols, danger combinations, and emergency resources.
Core Harm Reduction Principles
Harm reduction acknowledges that drug use occurs in society and focuses on minimizing associated health and social risks without requiring abstinence. The following principles are endorsed by public health authorities worldwide and inform the content on this page.
Test Your Substances
Reagent test kits (Marquis, Folin, Simon's) identify substances and detect adulterants. Fentanyl test strips are essential for any powder substance. Testing takes 2 minutes and can prevent fatal overdose.
Start Low, Go Slow
Potency varies significantly between batches and sources. Always begin with a small test dose, especially with new sources. Wait for the full onset before redosing. This is especially critical for opioids, stimulants, and psychedelics.
Never Use Alone
A trusted person who knows what you've taken can be the difference between life and death in case of adverse reaction. For situations where using alone is unavoidable, services like Never Use Alone provide remote monitoring.
Avoid Dangerous Combinations
Many drug combinations are acutely dangerous or fatal. CNS depressant combinations (opioids + benzodiazepines + alcohol) are responsible for the majority of drug-related deaths. Check the TripSit combination chart before mixing any substances.
Carry Naloxone
Naloxone (Narcan) is a life-saving opioid reversal medication available without prescription in many jurisdictions. Anyone who uses opioids or who may be present when others use them should carry naloxone and know how to administer it.
Know the Signs of Overdose
Opioid overdose: slow/stopped breathing, blue lips, unresponsive. Stimulant overdose: chest pain, seizure, extreme hyperthermia. Depressant overdose: unresponsive, very slow breathing. Act immediately — call emergency services.
Dangerous Combinations
The following combinations are documented as acutely dangerous or potentially fatal. This information is based on TripSit interaction data and academic pharmacology research.
| Combination | Risk Level | Mechanism |
|---|---|---|
| Opioids + Benzodiazepines | ⚠ DANGEROUS | Both depress CNS — synergistic respiratory depression can be fatal |
| Opioids + Alcohol | ⚠ DANGEROUS | CNS depressant combination — additive respiratory depression |
| Stimulants + MAOIs | ⚠ DANGEROUS | Risk of hypertensive crisis, serotonin syndrome, and cardiac events |
| MDMA + Lithium | ⚠ DANGEROUS | Significantly increased seizure risk documented in case reports |
| Cocaine + Alcohol | ▲ UNSAFE | Forms cocaethylene in liver — increased cardiotoxicity and duration |
| Cannabis + Psychedelics | ~ CAUTION | Can significantly amplify and destabilize psychedelic experiences |
Full interaction data: combo.tripsit.me — a free, evidence-based drug interaction checker.
Substance Testing Guide
Reagent testing is one of the most impactful harm reduction practices. Test kits are inexpensive (typically $10-20), widely available online, and take less than five minutes to use. They are legal in most jurisdictions and not illegal to possess anywhere this site is accessible.
Fentanyl Test Strips (FTS)
Immunoassay strips originally developed for urine testing, now used for substance testing. Dissolve a small amount in water and dip the strip. One line = fentanyl detected. Two lines = not detected. Test all powder substances, including MDMA, cocaine, and heroin, regardless of source.
Marquis Reagent
Purple/black reaction indicates MDMA or amphetamines. Orange indicates DXM or certain opioids. No reaction may indicate inert substance or unknown compound. Use with other reagents for confirmation.
Mecke Reagent
Blue-green indicates presence of MDMA, MDA, DXM. Used alongside Marquis for cross-verification. Helps distinguish between MDMA and cathinone substitutes (bath salts) which react differently.
Simon's Reagent
Specifically distinguishes MDMA (no reaction) from MDA (blue). Important because MDA has a significantly different safety and pharmacology profile despite similar appearance.
Emergency Resources
SAMHSA Helpline (US)
Substance Abuse and Mental Health Services Administration
1-800-662-4357
Free, confidential, 24/7 treatment referral service
Never Use Alone (US)
Hotline for people using opioids alone. Staff will call 911 if you stop responding.
1-800-484-3731
DanceSafe
Nonprofit harm reduction organization providing drug checking services, testing kits, and educational resources.
dancesafe.org
TripSit
Online harm reduction service, drug combination chart, and 24/7 chat support for people experiencing difficult drug experiences.
tripsit.me
The Loop (UK)
Drug checking service operating at festivals and events. Academic research-backed substance testing and safety information.
wearetheloop.org
Crisis Text Line
Text-based crisis intervention available 24/7 for substance-related or mental health crises.
Text HOME to 741741 (US)