Safer Injection Guide
Practical, non-judgmental harm reduction for people who inject drugs. If you choose this route of administration, sterile technique and overdose preparation can prevent the most common and most serious complications.
Injection is the highest-risk route of administration. Every safer alternative (oral, sublingual, nasal, rectal) reduces your risk of infection, vascular damage, overdose, and death. If you are not currently injecting, strongly consider a different ROA. If you are injecting, this guide exists to keep you alive and healthy.
Three non-negotiable rules: (1) Always use new, sterile equipment. (2) Never use alone \u2014 have someone present or call a Never Use Alone line. (3) Have naloxone ready if using opioids.
never share
Sharing any injection equipment transmits HIV and hepatitis C. Hepatitis C can survive on surfaces for up to 6 weeks.
Needles/syringesCookers/spoonsCotton filtersWaterTourniquetsRinse water
step-by-step safer technique
1. Clean workspace
–Wash hands thoroughly with soap and water for at least 20 seconds.
–Clean the preparation surface with an alcohol wipe.
–Lay out all supplies before you begin: syringe, cooker, cotton filter, sterile water, tourniquet, alcohol wipes, sharps container.
–Never prepare on dirty surfaces (bathroom floors, carpet).
–Never touch the needle tip or the inside of the syringe barrel.
2. Dissolve
–Use sterile water only (single-use ampoules, available at needle exchanges). If unavailable, freshly boiled and cooled water.
–Place the substance in a clean cooker (metal spoon or purpose-made).
–Add sterile water and dissolve completely. For substances that require heat, heat gently from below — do not boil.
–Some substances dissolve in cold water (cocaine, most stimulants). Avoid heating these unnecessarily.
–Never use tap water, puddle water, or toilet water. These contain bacteria that cause endocarditis, abscesses, and sepsis.
–Never lick the needle or use saliva as a solvent.
–Never share water, cookers, or filters — these transmit hepatitis C even when needles are not shared.
3. Filter
–Draw the solution through a clean cotton filter (purpose-made syringe filters are safest).
–If using cotton, use a small, tightly rolled piece of fresh cotton. Do not reuse cotton.
–Draw the solution slowly through the filter into the syringe to remove particulates.
–Unfiltered particles cause vein damage, abscesses, and can embolize to lungs.
–Reused cotton harbors bacteria and "cotton fever" (endotoxin contamination).
–Cigarette filters contain fiberglass — do not use these.
4. Choose injection site
–Best sites: antecubital fossa (inside of elbow), forearm veins.
–Rotate sites between uses. Never use the same vein repeatedly.
–Feel for veins before applying the tourniquet. A tourniquet makes veins more visible and palpable.
–Veins feel bouncy/springy when pressed. Arteries pulse. Tendons feel hard and ropelike.
–Never inject into the neck, groin, or feet unless you are experienced and have no alternatives. These sites carry higher risk of hitting arteries and nerves.
–Never inject into swollen, red, or painful areas — these may be infected.
–Do not inject into hands or wrists — nerves and tendons are very close to veins here.
5. Inject
–Clean the injection site with an alcohol wipe. Let it dry completely (wet alcohol stings and can introduce bacteria).
–Apply the tourniquet 2–4 inches above the injection site.
–Insert the needle bevel-up at a 15–30 degree angle in the direction of blood flow (toward the heart).
–Pull back the plunger slightly ("register"). Dark red blood flowing into the syringe confirms you are in a vein.
–Remove the tourniquet BEFORE injecting.
–Inject slowly. If you feel pain, swelling, or resistance, stop — you may not be in a vein.
–Bright red blood that pulses = artery. Remove needle immediately, apply firm pressure for 10+ minutes.
–Never inject if you cannot register (confirm venous access). Missing a vein causes tissue damage and abscesses.
–If it hurts or swells during injection, stop. Withdraw and try another site.
6. After injection
–Withdraw the needle and apply gentle pressure with a clean cotton ball or gauze.
–Do not rub — this increases bruising.
–Apply an adhesive bandage.
–Dispose of the syringe in a sharps container immediately. Never recap and reuse.
–Never recap needles — this causes needlestick injuries.
–Never flush syringes down toilets or throw them in regular trash.
–If the site becomes red, warm, swollen, or develops a lump in the following days, this may be an abscess — seek medical attention.
overdose prevention for IV use
Always do a test shot. Inject a small fraction of the prepared dose first. Wait 30\u201360 seconds. If it is stronger than expected, you have not injected the full amount.
Carry naloxone (Narcan) if using opioids. Naloxone reverses opioid overdose. It has no effect on non-opioid overdoses but cannot cause harm. Available OTC in many jurisdictions.
Never use alone. If you must use alone, call the Never Use Alone hotline:
1-800-484-3731. An operator stays on the line and dispatches EMS if you become unresponsive.
Fentanyl test strips. Test every batch. Fentanyl contamination is widespread and not limited to opioids \u2014 it has been found in cocaine, methamphetamine, and pressed pills.
Tolerance resets fast. After even a few days of abstinence, your previous dose can be fatal. Always restart at a fraction of your prior dose after any break.
signs of complications
AbscessSymptoms: Red, warm, swollen area that is painful to touch. May have pus.
Action: Seek medical care. Abscesses require drainage — they do not resolve on their own and can become life-threatening sepsis.
Missed hit (extravasation)Symptoms: Swelling, pain, and hardness at the injection site during or after injecting.
Action: Apply warm compresses. Do not try to re-inject in the same area. If swelling worsens or skin changes color, seek medical care.
Arterial hitSymptoms: Bright red blood, pulsing flow, immediate intense pain radiating to hand.
Action: Remove needle immediately. Apply firm, direct pressure for 10–15 minutes. Do NOT use a tourniquet. If pain, numbness, or color change persists, this is a medical emergency.
Cotton feverSymptoms: Fever, chills, body aches within 20–30 minutes of injecting. Usually from reused cotton filters.
Action: Generally self-resolving within 6–12 hours. Stay hydrated. If fever exceeds 39°C / 102°F or does not resolve, seek medical care (may be endocarditis).
Endocarditis (heart infection)Symptoms: Persistent fever, night sweats, fatigue, new heart murmur, weight loss over days to weeks.
Action: This is a medical emergency. Requires hospitalization and IV antibiotics for 4–6 weeks. Untreated, it is fatal. Do not delay.
where to get clean supplies
Needle exchange programs (SEPs/SSPs)Free sterile supplies, sharps disposal, often also testing for HIV/HCV, naloxone distribution, and referrals. Search "syringe service program" + your city.
PharmaciesMany states/countries allow OTC syringe purchase without a prescription. Prices are typically low. Ask at the pharmacy counter.
Online harm reduction organizationsNEXT Distro (US), The Loop (UK), and similar organizations provide supplies by mail in some regions.
Vending machinesSome cities have 24/7 syringe vending machines. Check your local harm reduction organization.
This guide is not an endorsement of injection drug use. It is a recognition that people who inject drugs deserve accurate health information. Harm reduction saves lives by meeting people where they are.
If you are considering stopping or reducing injection drug use, medication-assisted treatment (buprenorphine, methadone, naltrexone) has the strongest evidence base for opioid use disorder. Crisis resources →