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Fentanyl-Laced Heroin

Fentanyl is a powerful synthetic opioid with 50 times more potent effects than heroin.5 While heroin use on its own can be dangerous, it’s even more risky when fentanyl is in the mix.1 Whether you use fentanyl and heroin intentionally or unintentionally, the combination can increase the risk of potentially fatal overdose.1 Understanding how fentanyl and heroin can be a deadly combo and how to seek help can be essential in starting your journey to recovery.

Understanding Fentanyl and Heroin

Illicitly manufactured fentanyl and heroin are both powerful illegal opioids with a similar range of adverse effects, such as pronounced sedation, decreased levels of consciousness, and slowed breathing.1, 2  However, fentanyl has significantly more potent opioid effects than heroin, so the combination of these two substances can present an even greater risk of breathing problems and lethal overdose.1 Outside of overdose risks, both fentanyl and heroin carry a high potential for physiological dependence and addiction (or, in diagnostic terms, an opioid use disorder).1

Dangers & Risks of Mixing Fentanyl with Heroin

People who use heroin may not realize that they might be using fentanyl-laced heroin, as illicit drug manufacturers and dealers increasingly cut heroin (and other street drugs) with fentanyl to increase the user’s high and their own profits.1 As the awareness of the subjectively different, more potent fentanyl high has grown, some people may intentionally seek out fentanyl laced heroin to deliver a more intense rush than heroin alone.3

It’s important to be aware that in either case, using heroin mixed with fentanyl can easily overwhelm a person’s body, since fentanyl is much stronger than the heroin that they might be accustomed to.1 This means that using a heroin-fentanyl mixture can present a significantly increased risk of overdose, as well as other harmful consequences.1

Fentanyl and Heroin Overdose

Opioids carry a high potential for compulsive misuse, addiction, and overdose. Opioid overdose in particular has become a major public health crisis in the United States, with more than 80,000 reported deaths from an overdose involving some type of opioid in 2021.9 Heroin and fentanyl are no different, and misuse can result in a potentially life threatening overdose.4 If you suspect that you or someone nearby is experiencing an opioid overdose it is important to contact 911 emergency medical services immediately.1

Fentanyl and Heroin Overdose Symptoms

An opioid overdose can be life-threatening and often requires immediate medical attention.4 Due to fentanyl and heroin both being opioids, overdose symptoms may be indistinguishable from each other, though fentanyl overdose symptoms may be far more severe due to the potency of the drug.

Fentanyl and heroin overdose symptoms may include:

  • Small, constricted pinpoint pupils.4
  • Sleepiness or loss of consciousness.4
  • Slow, weak, or no breathing.4
  • Choking or gurgling sounds.4
  • Limp body.4
  • Cold and/or clammy skin.4
  • Blue or purplish skin, especially in their lips and nails.6

How to Stop a Fentanyl and Heroin Overdose

As mentioned above, it’s crucial to call for help right away if someone displays any of the signs of an opioid overdose.4 Additionally, you should provide naloxone, sometimes available under the brand name Narcan, if you have access to it.4

Narcan is a lifesaving medication that can help reverse the effects of an opioid overdose while you are waiting for emergency services to arrive, but it must be promptly administered.8 The effects of naloxone are temporary, which is why people who have overdosed still need emergency medical attention.8

How Does Fentanyl Get into Heroin?

Oftentimes, heroin obtained on the street may be cut or laced with extremely potent fentanyl, resulting in somebody with relatively lower opioid tolerance putting themselves at increased risk of an overdose.4 Fentanyl test strips are inexpensive, easy to use, and can be lifesaving.4 They can help determine whether there is fentanyl in heroin within just a few minutes.4 According to the Centers for Disease Control and Prevention, fentanyl test strips are generally used as follows:5

  • Put a small amount (at least 10mg) of your drugs aside in a clean, dry container.
  • Add ½ teaspoon of water to the sample and mix together.
  • Place the wavy end of the test strip down in the water and let it absorb for about 15 seconds.
  • Take the strip out of the water and place it on a flat surface for 2-5 minutes.
  • Read the results.

If you see a single pink line on the left, the strips have detected the presence of fentanyl and you are much safer if you do not use it.5  Two pink lines mean that the strips have not detected the presence of fentanyl.5 However, you should be aware that fentanyl test strips do not detect even more potent synthetic opioids like carfentanil, which can itself also lead to deadly overdose.5

Finding Treatment for Fentanyl and Heroin Misuse and Addiction

If you or someone you care about use heroin and fentanyl, you should know that effective treatment is available to help people safely stop using opioids and regain control of their lives.1 When you’re ready to start the recovery process, you might first wish to consult your doctor to discuss your situation, have an evaluation to receive a diagnosis, and ask for referrals to rehab.

You can also browse thousands of rehab facilities across the nation using our fentanyl support directory. Please call our free, confidential helpline at to speak to a caring and knowledgeable admissions navigator, learn more about your rehab options, and instantly verify your insurance benefits.

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