Harm Reduction

Testing, dosing, and preparation sit alongside tolerance, dependence, and recovery. This is the practical layer of the encyclopedia.

In an emergency

Someone unconscious, not breathing, or seizing? Call 911 999 112 now. You won't get in trouble for calling — most places have Good Samaritan laws.

In a mental-health crisis: call or text 988 in the US, or your local crisis line.

The non-negotiables

Test everything. Pressed pills and powders lie about what they are. A reagent kit and a fentanyl strip cost less than one hospital visit.

Start low, go slow. You can always take more; you can never take less. Wait for full onset before you redose.

One thing at a time. Every combination is effectively a new drug — most fatal overdoses involve more than one substance.

Weigh it, don't eyeball it. For many substances the gap between a dose and an overdose is a few milligrams. Use a milligram scale.

Never use alone. Have a sober sitter who knows what you took — or call Never Use Alone at 1-800-484-3731 and stay on the line while you use.

Set and setting outrank the dose. Your headspace and surroundings shape the experience more than the milligrams do.

Tolerance loss kills. After a break, the dose you used to take can stop your breathing. Re-titrate from the bottom of the range.

Cutting down or stopping is harm reduction. Support is free, and there is no threshold you have to cross before asking for it.

Most harm is decided before you dose. Test it, weigh it, and learn what it doesn't mix with.

Once it's begun, the job is to stay safe — and to know what to do if it turns hard.

The comedown isn't the end. Space it out, watch for dependence, and use the recovery tools whenever you want them.

Essential reference guides. Expand any card for key data — open the full guide for complete details.

Independent harm-reduction organizations: testing services, factsheets, and peer support.