When Charli XCX and Troye Sivan’s Sweat Tour came to my hometown of Boston two years ago, I balked at the ticket resale price and decided not to go. On the day of the event, I scrolled through Instagram stories hours before the show, looking at my friends’ carefully curated outfits and regretting my decision. 

Suddenly, my scrolling was interrupted by a burst of notifications. I’m part of a volunteer group that plans overdose prevention trainings in nightclubs, community centres and classrooms. That afternoon, our chat suddenly became very active. A community member had reached out to alert us that party drugs he purchased for the show had tested positive for fentanyl—a result he confirmed using free test strips he picked up at one of our events. He hoped sharing this news might help others in our network avoid harm if a fentanyl-laced batch was indeed circulating in the city.
 

Our volunteers quickly alerted our community, through texts and a PSA on Instagram, to test all concert party drugs for fentanyl. “It only takes a minute to make sure you’re safe. ALWAYS test. NEVER take the risk,” the post read. 

Before long, others confirmed they too had positive fentanyl tests. We notified city public health officials about the incident and continued urging people to test in order to avoid a potential overdose that night.
 

You’ve probably heard of fentanyl. But you might not know about the less-talked-about fentanyl test strips—the single-use overdose prevention tool our community member used to keep himself and others safe that day. These test strips are designed to quickly detect fentanyl in powders, crushed pills, tablets or other drug forms, and are often distributed for free by harm reduction and public health organizations. Most importantly, they can save lives. 
 

Fentanyl test strips are simple to use, and as a harm reduction worker, I want more people to be able to understand how to do so. So for Script I’ve put together a guide to these vital harm reduction tools, and how you might use them to keep yourself safe. 
 

What are fentanyl test strips?

Fentanyl is an opioid that has made its way into the illicit drug market. Given the drug market’s unregulated nature, people who use drugs may not know exactly which ingredients are in the substances they plan to consume. Fentanyl’s presence in a drug is often unknown to the consumer, and a small amount of fentanyl can potentially cause a fatal overdose.

As mentioned above, fentanyl test strips are a single-use overdose-prevention tool designed to detect fentanyl in powders, crushed pills, tablets or other drug forms that can be diluted in water within minutes. Test strips typically come in a foil packet and include a single paper strip. Sometimes test strip packets also come with a plastic scoop to measure a drug sample for testing.
 

How do test strips prevent overdose?

Given fentanyl’s potentially harmful nature, it’s important to test your drugs to know if fentanyl is present. Test strips allow people to test their supply prior to consumption, effectively allowing the consumer to both identify and consciously avoid fentanyl. Unlike resources like community drug-checking services, fentanyl test strips can be used at home. Anyone planning to consume an unregulated drug (in other words, something they didn’t purchase from a pharmacy) might use test strips to detect and avoid consuming fentanyl.
 

Mike Selick, director of Capacity Building and Community Mobilization at the National Harm Reduction Coalition notes that “an official testing centre is a better option, but a test strip will do the trick [to detect fentanyl].”
 

It’s important to note that false positives or false negatives may occasionally occur when testing your drugs for fentanyl. Still, test strips are generally highly accurate. Following test-strip instructions accurately can minimize likelihood of inaccurate results. 
 

Where can I get test strips?

Like condoms or other public health supplies, fentanyl test strips are often available over the counter at pharmacies or for free at health clinics. The National Harm Reduction Coalition has a free tool to find harm reduction programs and resources near you. You can check your local health clinic’s website to see if they stock fentanyl test strips, or order common brands online such as BTNX Rapid Response, DanceSafe and WiseBatch.
 

Are test strips legal?

Fentanyl test strip legality varies by region. Some U.S. states such as Iowa, North Dakota, Idaho and Texas still classify fentanyl test strips as illegal drug paraphernalia. In Canada, meanwhile, test strips are legal. 
 

How do I use fentanyl test strips?

It’s important to note that directions for fentanyl test strips (the amount of water required to perform a test, wait time to read results) may vary by brand. I’ve outlined some general instructions below, but be sure to follow your test strip’s directions exactly for accurate testing. Many test strips feature a QR code linking to step-by-step instructions, visual aids and additional instructions for testing specific kinds of drugs.
 

To start, you will need a fentanyl test strip, a drug sample and water. Most drugs require half a teaspoon (2.5 ml) of water to test, but some require more. Ensure the test strip is not expired or tampered with and you have a distraction-free and clean environment to test.
 

Measure at least 10 mg of the drug and place the sample into a clean container. Be sure to thoroughly mix your sample. Many harm reduction groups liken fentanyl in drugs to chocolate chips in a cookie; just as one piece of a cookie might have several chocolate chips or no chocolate chips, part of a drug sample might contain fentanyl while another part does not. 
If you are testing pills, every pill should be tested individually. One negative result may not represent the entire batch.

Add water and stir thoroughly to dilute the sample. Then, place the patterned end of the strip into the water for about 15 seconds. Your result will appear in about 5 minutes or less. Dispose of the test strip after reading your results. Do not reuse test strips.
 

How do I know if fentanyl is present?

If fentanyl is present, the positive result will be indicated by one line on the paper strip. A negative result will be indicated by two lines. The package instructions will confirm this, so make sure you check directions to confirm you are reading the result correctly. 
 

If the sample tests positive for fentanyl, you can choose to avoid consuming that substance. Be sure to alert anyone else who may be planning to consume from the same batch. It’s important to note that a negative test result doesn’t necessarily mean 100 percent “safety.” Test strips will not indicate purity, the amount of fentanyl present in a substance or if other potentially harmful substances are present.
 

Many overdose prevention organizations encourage people who use drugs to take precautions in addition to drug testing. Selick notes, “If you’re going to engage in any drug use in 2026, learn how to use Narcan [naloxone] … and put time between your use and your friends’ use, even if it’s only a few minutes.”

Health Canada has published guidelines and limitations online regarding testing.
 

The bottom line 

Fentanyl test strips are not an end-all solution. That said, they can be a convenient and helpful tool for increasing safety around drug consumption. When in doubt, speak to a trusted healthcare provider about substance use. Also, investigate drug-testing programs that may offer more comprehensive testing and results for safer consumption.