Harm reduction
Avoiding non-medical substance use avoids its associated risks. Do not stop prescribed medicines without medical advice. This page is for people who may use them anyway, and for anyone who wants to understand the risks. It collects general, evidence-informed principles for reducing harm. It is educational information only, not medical or legal advice, and not an encouragement to use any substance.
In an emergency
If someone is unconscious, having trouble breathing, having a seizure, overheating, experiencing chest pain, or cannot be woken, call your local emergency number immediately. Tell responders what was taken if you know it. Follow the emergency dispatcher's instructions. Police attendance and legal protections vary by jurisdiction.
- If the person is unresponsive and not breathing normally, including gasping, start CPR and use an AED if available. Follow the emergency dispatcher and AED instructions.
- If the person is unconscious but breathing normally, place them in the recovery position and keep checking their breathing. Tell the dispatcher about any suspected injury.
- For a suspected opioid overdose (slow or stopped breathing, blue lips, pinpoint pupils), give naloxone if available and follow the product instructions for repeat doses. Continue dispatcher-guided breathing support or CPR as instructed. Emergency assessment is still needed if they wake up because breathing problems can return.
- For overheating on stimulants/MDMA, move the person to a cool place and cool their skin while help is on the way. Confusion, seizures or collapse require urgent medical help. Offer small sips only if they are fully alert and can swallow. Do not give fluids to an unconscious or confused person, and do not force large amounts of water.
- Never leave someone alone to "sleep it off" if they are not fully responsive.
Core principles
- Research first. Know the substance, its typical dose range, onset, duration, and common interactions before, not after.
- Test your substances. Reagent tests can indicate some substances but cannot establish purity, dose or the absence of other drugs. Laboratory drug checking provides more information where available. Fentanyl test strips have detection limits, and a negative result does not prove a sample is safe.
- Start low, go slow. Begin well below a typical dose, especially with a new batch or substance, and wait for the full effect before considering more. Delayed onset and accumulation can make redosing dangerous. A low initial dose does not establish safety.
- One thing at a time. Combining substances, including alcohol and prescription medication, is where much serious harm happens (see below).
- Don't use alone. Have a sober, trusted person present who knows what you took and what to do if something goes wrong.
- Mind the basics. Eat, hydrate sensibly (not excessively), rest, and avoid use when physically unwell.
Dangerous combinations
Some combinations are far riskier than either substance alone. A few well-documented examples:
- Depressants together (opioids + benzodiazepines + alcohol, GHB/GBL with any of these) can suppress breathing and are a leading cause of fatal overdose.
- Stimulants with stimulants increase strain on the heart and risk of overheating, anxiety, and cardiovascular events.
- Serotonergic combinations can cause life-threatening serotonin toxicity, particularly when an MAOI is combined with a serotonin releaser such as MDMA or a serotonin-reuptake inhibitor. Risks vary by the specific drugs. Do not assume all psychedelics or antidepressants interact in the same way.
- Tramadol, bupropion, and some other drugs lower the seizure threshold and interact unpredictably.
When in doubt, do not mix. Check an up-to-date interaction reference and consult a medical professional about prescription medication.
Dose, set, and setting
- Dose depends on the substance, the salt form, your body, tolerance, and route. Reference ranges on compound pages are not "safe" doses or recommendations.
- Set: your mindset, expectations, and mental health strongly shape the experience. Avoid use during acute distress or crisis.
- Setting: a safe, familiar environment with people you trust reduces the chance of accidents and difficult experiences.
Tolerance, frequency, and dependence
Repeated use can cause tolerance and dependence, depending on the substance. No fixed interval between uses guarantees protection from harm. Increasing dose to chase a previous effect is a common path to harm. If use feels difficult to control, seek professional support. Abrupt withdrawal from alcohol, benzodiazepines, GHB or some prescribed medicines can be dangerous. Seek medical advice before stopping after regular use.
Finding help and reliable information
Local services vary widely by country and region. Look for: your national or regional drug-checking and harm-reduction services, poison information centres, sexual-health and needle-exchange programmes, and confidential drug helplines. For mental-health crises, contact a local crisis line or emergency services. A doctor or pharmacist can advise on interactions with prescribed medication in confidence.
Sources
Educational use only. This page does not provide medical or legal advice and does not endorse substance use. Information can be incomplete, jurisdiction-dependent, and subject to change. Severe or unexpected symptoms require urgent medical attention, and current legal questions should always be verified against official authorities.