What are opioids?

Opioids are a group of natural and synthetic substances that are primarily used for pain management. Opioids function by binding to naturally occurring opioid receptors in the brain and spinal cord. Once these molecules bind to their receptors, they block signals being sent to and from the brain and spinal cord, thus producing their pain-relieving effects.

Medically, opioids have long been used to treat acute (sudden and short-term) pain due to a surgery or injury, chronic (long term) pain, or cancer-related pain. Prescription opioids include medications such as codeine, morphine, oxycodone, hydrocodone, methadone, and medical fentanyl. Illicit opioids, which are illegal to produce, sell, buy, or use, include substances like heroin or illicit fentanyl.

Even if opioids are used as prescribed by a medical professional, they pose a high potential for addiction, also known as opioid use disorder. Opioids cause a significant surge of dopamine in the brain’s reward complex, leading to dependence, increased tolerance, and withdrawal symptoms when stopping use.

Natural and semi-synthetic opioids are derived from the opium poppy plant, also known as Papaver somniferum.

Short-term effects of opioid use

  • Pain Relief

  • Feelings of euphoria or relaxation

  • Difficulty concentrating or making decisions

  • Slow or shallow breathing

  • Drowsiness

  • Loss of consciousness

Fentanyl

Fentanyl is a synthetic opioid that is up to 100 times stronger than morphine and 50 times stronger than heroin. The amount of fentanyl shown on the tip of a pencil, 2 milligrams, is the lethal dose of fentanyl for the average adult. To put that into perspective, fentanyl delivered in a medical setting is typically dosed in micrograms, which are one-thousandth of a milligram. Thus, fentanyl is an extremely potent substance that can lead to fatal consequences even at extremely small doses.

According to the DEA’s 2025 National Drug Threat Assessment, over 61.1 million illicit pills containing fentanyl were seized in 2024. Out of these 61.1 million pills, 5 in 10, or 50%, contained a lethal dose of fentanyl (over 2 mg).

Any illicit pill or powder can contain trace amounts of fentanyl that are not visible to the human eye. Fentanyl is mostly laced in pills and powders such as cocaine, heroin, xylazine, and other substances.

It is impossible to tell if drugs have been mixed with fentanyl unless you use fentanyl test strips. Fentanyl test strips are diagnostic tools to determine whether your substance has been laced with fentanyl.

Counterfeit pills

Images sourced from DEA.

Using fentanyl test strips

Source: BirdieLight.

Fentanyl Test Strips (FTS) do not measure how much fentanyl is in a drug sample, they only detect if fentanyl is present.

Fentanyl is often unevenly mixed with other drugs. This means one part of a drug might have no fentanyl while another part could be deadly. Pills should be crushed entirely and tested before use. Test every part of the drug you plan to use to stay safe.

Opioid overdose

Opioids act as central nervous system depressants, meaning they slow the body’s breathing and heart rate. An opioid overdose occurs when someone takes too much of an opioid or combines it with other depressants, such as alcohol, benzodiazepines, or muscle relaxants, causing breathing to slow to a dangerously low level or stop altogether. Without prompt treatment, an overdose can quickly lead to loss of consciousness, brain injury, and death.

The opioid overdose epidemic in the U.S.

The United States continues to face a devastating opioid overdose epidemic that has claimed hundreds of thousands of lives over the past 25 years. Since the 1990s, opioid-involved overdose deaths have risen dramatically, driven by three distinct waves: the first fueled by prescription opioids in the late 1990s, the second by heroin beginning around 2010, and the third by synthetic opioids, primarily illegally made fentanyl, starting in 2013. Although 2023 marked the first decline in opioid-involved deaths since 2018, with rates falling about 4% from the previous year, the crisis remains severe. Nearly 80,000 people died from opioid overdoses in 2023, accounting for roughly three-quarters of all drug overdose deaths. Synthetic opioids like fentanyl continue to dominate the illegal drug supply, often mixed with other substances such as xylazine or stimulants, increasing the risk of fatal overdose.

Source: CDC

Signs of an opioid overdose

Small, pinpoint pupils

Slow, irregular, or stopped breathing

Limp arms and/or legs

Unconscious and/or unresponsive

Blue lips/skin, pale and clammy skin

Slow or faint heartbeat

If you see these signs, call 911 and administer naloxone IMMEDIATELY.

Naloxone

Naloxone is a life-saving medication used to reverse an opioid overdose. Naloxone works as a competitive antagonist to opioids, binding to opioid receptors and kicking opioids off of receptors to immediately reverse an overdose. When naloxone successfully reverses an opioid overdose, it causes the person experiencing the overdose to enter an immediate state of opioid withdrawal. Opioid withdrawal symptoms include, but are not limited to: anxiety, restlessness, aches, chills, fever, diarrhea, nausea, vomiting, and excessive sweating. Thus, when administering naloxone, it is important to note that the person experiencing the overdose may be agitated or anxious upon regaining consciousness.

Naloxone is approved for use in two forms, a nasal spray and an injectable into the muscle or under the skin. The most common publicly available brand of naloxone is Narcan®, a 4 mg naloxone nasal spray. Naloxone can be found at most local pharmacies (no prescription required). For a map of all locations providing free naloxone within Cook County, click here.

Source: Narcan.com

How to use naloxone

Step 1: Check if you suspect an overdose.

  • The person will not wake up or is very sleepy or is not breathing well

  • Yell “Wake up!”

  • Shake the person gently

    If the person is not awake, go to Step 2

Step 2: Give 1st dose in the nose

  • Hold the nasal spray device with your thumb on the bottom of the plunger

  • Insert the nozzle into either nostril

  • Press the plunger firmly to give the first dose

  • 1 nasal spray device contains 1 dose

Step 3: Call 911

  • Call 911 immediately after giving the 1st dose

Step 4: Watch & Give

  • Wait 2-3 minutes after the 1st dose to give the medicine time to work

  • If the person wakes up: Go to Step 5

  • If the person does not wake up:

    • Continue to give doses every 2-3 minutes until the person wakes up

    • It is safe to keep giving doses

Step 5: Stay

  • Stay until ambulance arrives: even if the person wakes up

  • Give another dose if the person becomes very sleepy again

  • You may need to give all the doses in the pack

Images sourced from: LBL040253-p9