How to test for fentanyl

Everything you need to know about how to test for this potentially deadly compound.

Ophelia team
Fentanyl test strip
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Fact checked by
Arthur Robin Williams, MD

Fentanyl is a very powerful synthetic opioid. Even though it has pharmaceutical uses, illegal fentanyl often gets mixed with heroin or cocaine to increase the drug’s effects. And people who aren’t aware of it being mixed into their supply are at a much greater risk of overdosing.

Overdose deaths spiked in the first half of 2020 before decreasing later in the year—but they spiked again in the first six months of 2021 and exceeded the previous year’s levels by 53,000. Fentanyl test strips offer a reliable method for identifying this potentially deadly compound, but they can be hard to find due to a combination of bureaucracy and misguided stigma. Ridiculous, isn’t it? 

What are fentanyl test strips?

Fentanyl test strips (FTS) are inexpensive, easy-to-use tools that determine whether a drug batch contains fentanyl. These small strips of paper react to even low levels of the substance in pills, powders, or injectable drugs. A positive result on the test strip alerts the individual to the presence of fentanyl in their drugs before ingestion. That way, they can make an informed decision about their drug use. 

Keep in mind that these test strips only reveal whether the drugs contain fentanyl. If the compound is present in the drugs, the test strips won’t indicate the potency level or quantity. Additionally, there are many versions of fentanyl in the illicit drug supply, and basic test strips can miss variants that could also be lethal.

Using fentanyl test strips is one way to help prevent an opioid overdose. The use of fentanyl test strips should be paired with other risk reduction practices to reduce the chance of overdosing even further. 

How to test for fentanyl

To test your drugs for fentanyl, you’ll need a fresh test strip and at least a trace amount of the drugs. The best way to use the test strips is to dissolve all the drugs in question in water. Since fentanyl isn’t always evenly distributed throughout the product, this method guarantees that you won’t inadvertently miss the fentanyl with the FTS. 

If you can’t test this way, you can add water to a very small amount of your drugs and test that solution. 

When testing pills, crush one on a clean surface and place some of the resulting powder in a clean, dry container. A soda bottle top works well. With drugs in powder form, you can use a small amount of the powder.

You can use the drug residue left in the cooker after preparing an injectable dose. Add enough water to dissolve the drugs into the container or cooker. For ecstasy, MDMA, and methamphetamines, this is about 1 teaspoon of water per 10 mg of crystal or powder. For any other drugs, use just half a teaspoon of water. Stir the drugs and the water well to combine them. 

Next, take the new fentanyl test strip and place the wavy side into the drug/water mixture. Wait for 15 seconds before taking the test strip out of the water and set it aside. 

You should see the test results within five minutes, usually after one or two minutes. 

If there are two lines in the middle of the test strip, that indicates that the drugs do not contain any fentanyl. If there is only one line in the middle of the test strip, that means that the drugs do contain fentanyl. 

You may be wondering, how accurate are the test strips? A 2018 study by researchers at Brown University, Boston Medical Center, and Johns Hopkins University found that fentanyl test strips are accurate at detecting fentanyl. Getting a false negative is unlikely, so you can be confident in the accuracy of your test results. 

Where can you buy fentanyl test strips?

In 2021, The Centers for Disease Control and Prevention (CDC) and the Substance Abuse and Mental Health Services Administration (SAMHSA) announced that federal grant recipients may use federal funding to buy rapid fentanyl test strips. As a result, fentanyl test strips are generally available from syringe exchange programs or other harm reduction programs. 

The stigma around addiction may prevent people from accessing these resources, though. Buying online offers more privacy, and the strips are available for about $1 each from sites like DoseTest and Bunk Police.  

What are fentanyl overdose symptoms?

The greatest danger of fentanyl in drug batches is that it significantly increases the chances of overdose. Familiarizing yourself with the various fentanyl overdose symptoms can help you identify an overdose and get help if necessary. Common overdose symptoms include:

  • Lowered heart rate
  • Low blood pressure
  • Changes in pupil size
  • Depressed breathing
  • Blue lips and/or fingernails
  • Dizziness
  • Drowsiness
  • Reduction or loss of consciousness

In particular, look for the “opioid overdose triad of symptoms.” Together, lowered consciousness, respiratory distress, and pinpoint pupils indicate a possible opioid overdose. 

Learn more

The SAMHSA site contains a variety of additional resources for recovery support services, including information about opioid addiction and fentanyl. 

For help managing addiction treatment at home, learn about Ophelia’s private, personalized approach.


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