Why mixing substances increases risk
Safety & Harm Reduction — Guide 10 of 25

Combining substances can change their effects and make an emergency harder to predict. Prescription medicines count too.

Watch for dangerous combinations
Opioids combined with alcohol or sedating medicines can dangerously slow breathing. Examples of sedating medicines include some sleeping pills and benzodiazepines. A stimulant does not cancel out a depressant or make someone safe to drive.

Ask before combining
- Tell a pharmacist or clinician about prescriptions, over-the-counter medicines, supplements, alcohol, and other substances.
- Ask: “Could this combination affect my breathing, alertness, or heart?”
- Take medicines as prescribed and do not share them.
- Avoid adding another substance to manage an unwanted effect.

If something goes wrong
Difficulty waking, abnormal breathing, chest pain, or a seizure requires emergency help. Tell responders what may have been taken, including approximate timing if known. You do not need a complete list before calling.

If you are helping someone
Help someone check interactions with a pharmacist; do not suggest a substance to counteract another.

WARN (OTHERS): After immediate care is covered, share dated advisories or observed concerns. Say what is confirmed and what is uncertain. Protect people’s privacy. Emergency care comes first. Never share someone’s name, identifying photo or private health details.

Your next step
Check one medication or substance interaction with a pharmacist.

Learn more
Health Canada — Opioid overdose
https://www.canada.ca/en/health-canada/services/opioids/overdose.html

CDC — Stimulant guide
https://www.cdc.gov/overdose-prevention/media/pdfs/2024/03/cdc-stimulant-guide.pdf

Current guide: https://therealdopeproject.com/safety-guides/why-mixing-substances-increases-risk

The Real DOPE Project — Safety Is for Everyone.

Contact: therealdopeproject@gmail.com

Resource text updated: 2026-10-13. Earlier sources retain their individual review dates.

General education, not individual medical advice or first aid certification. In an emergency, call 911 and follow the dispatcher and your exact kit instructions.

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