If your loved one is using any illicit drug — including those they do not believe contain fentanyl — fentanyl test strips are one of the most important harm reduction tools available. They are cheap, widely accessible, and can tell someone whether the substance they are about to use contains fentanyl before they use it. That information saves lives.

Why Fentanyl Is Now Everywhere

Fentanyl is a synthetic opioid approximately 50 times more potent than heroin and 100 times more potent than morphine. It was originally developed for post-surgical pain management and palliative care. Over the past decade, illicitly produced fentanyl has become the primary driver of drug overdose deaths in the United States and is increasingly present in drug supplies across Europe and elsewhere.

Why is it so prevalent in the illicit supply? Because it is extremely cheap to produce, extremely potent in very small amounts, and therefore highly profitable to add to other substances — including cocaine, methamphetamine, counterfeit prescription pills, and even cannabis products. Crucially, it is invisible and odourless. Without a test, there is no way to know it is there.

What Fentanyl Test Strips Are

Fentanyl test strips (FTS) are thin paper strips, originally developed to test urine for fentanyl metabolites. They have been repurposed for harm reduction use: dissolving a small amount of a drug in water and dipping the strip will reveal whether fentanyl (or fentanyl analogues) are present.

• One line on the strip = fentanyl detected
• Two lines on the strip = fentanyl not detected
• Cost: approximately $1–2 per strip, or free from many harm reduction organisations

How to Use Them

1. Dissolve a small amount of the substance in water — approximately ¼ teaspoon of water per dose amount that would typically be used
2. Dip the test strip for 15 seconds, strip end down
3. Lay the strip flat and wait 2–5 minutes
4. Read the result: one line = positive for fentanyl; two lines = negative

Legality

In the United States, fentanyl test strips were classified as drug paraphernalia under many state laws, making possession illegal in some states. This has changed significantly in recent years — as of 2024, a large majority of US states have removed test strips from paraphernalia laws or explicitly legalised them. Check the current status in your state at harmreduction.org.

In the UK, fentanyl test strips are legal and available through harm reduction services.

Where to Get Fentanyl Test Strips

• NEXT Distro (nextdistro.org) — free harm reduction supplies by post to most US states
• Local harm reduction organisations — needle exchanges, drug checking services, community health centres
• Online retailers — BTNX is the most widely used manufacturer; strips are sold online
• In the UK: available through drug services and some pharmacies under NHS harm reduction programmes

Talking About Test Strips With Your Loved One

Introducing fentanyl test strips to someone you love who is using requires a pragmatic approach. You are not condoning their drug use. You are trying to ensure they survive long enough to reach recovery.

The framing: “I know you’re using. I’m not going to pretend otherwise. I need you to be alive. These test strips could tell you whether what you have contains fentanyl. Will you use them?”

For many families, harm reduction — meeting people where they are rather than where you want them to be — is the approach that keeps someone alive through the period before they are ready for recovery.

See also: Naloxone: A Guide for Families →