A fentanyl patch may be small, but it contains a powerful opioid that delivers medication around the clock. This long-acting design can help control severe pain and persistent discomfort, like cancer pain. But fentanyl patches also carry serious risks requiring careful medical supervision, especially for people with opioid use disorder (OUD) or a history of substance use.

Understanding the risks, side effects and warning signs of overdose from fentanyl patches can help people and their caregivers stay informed and safe during treatment. Here’s what to know about this pain management method.

What Are Fentanyl Patches?

The fentanyl transdermal patch, also known as Duragesic, is a small, sticky patch placed on the skin. Fentanyl is a synthetic opioid drug that works by changing how the brain responds to pain. Transdermal means that it slowly releases the fentanyl into the body through the skin over several days.

Doctors prescribe fentanyl patches to people who already take opioids and have developed opioid tolerance. Tolerance is when the body gets used to the same dose of opioids over time and may need a stronger dose to control pain.

People living with severe chronic pain or cancer pain often use fentanyl patches. People who have mild or short-term pain, and those who have never used opioids before, generally should not use these patches.

Why Medical Supervision Is Needed

Fentanyl is one of the strongest opioid medications available. It’s 100 times more potent than morphine. Because of how strong fentanyl is, even small changes in how you use the patch can have serious effects.

The patch slowly releases fentanyl continuously, which means the dose builds up in the body over time. Healthcare providers who prescribe fentanyl patches usually start at a lower dose to see how the medication works for you.

Fentanyl patches affect the central nervous system (CNS), which controls breathing and other important bodily functions. Too much fentanyl can slow these functions down, leading to slowed breathing and other serious side effects. Because of these risks, people who use a transdermal fentanyl patch should have regular follow-up visits with their healthcare team while on the treatment.

Factors That Can Increase Overdose Risk

Several factors can affect how fentanyl enters the bloodstream through a transdermal patch. Some of these factors can raise the risk of overdose by increasing how much fentanyl the patch releases into the body.

Things that may raise your risk of overdose include:

• Heat exposure — If the patch is exposed to extreme heat, such as hot tubs, heating pads, saunas, or electric blankets, it may release too much medication into your body at once. Having a high fever can also increase fentanyl absorption.
• Incorrect use — Cutting the patch, applying the patch to broken or irritated skin or skin that has been exposed to radiation, or chewing or swallowing the patch can release the medication more quickly or all at once.
• Accidental exposure — Used patches can contain leftover fentanyl. It’s important to fold a used fentanyl patch in half with sticky sides together and flush it down the toilet to help prevent other people from being exposed to the drug.
• MRI scans — Since some transdermal patches contain metallic components, MRI scans can cause skin burns if you don’t remove the patches beforehand.

Even after you remove a fentanyl patch, the medication can stay in your body for quite some time. For this reason, you should always carefully follow the instructions on your patches to avoid harmful side effects.

Potential Side Effects of a Fentanyl Patch

Like many opioid medications, fentanyl patches can cause side effects. Some are mild, but others may need medical attention. It’s important to know what the side effects are and when to contact your healthcare provider or emergency responders.

Common Side Effects

Common side effects of fentanyl patches include:

• Nausea, vomiting, and constipation
• Drowsiness or sedation
• Dizziness
• Headache
• Loss of appetite
• Skin irritation

Some people may also have confusion or, in rare cases, hallucinations.

Many of these side effects may improve over time with diet changes or dose adjustments. They may also improve as your body gets used to the medication. However, you should talk to your healthcare provider if you have any side effects that become difficult to manage.

Serious Side Effects and Overdose Warning Signs

While many side effects are uncomfortable but not dangerous, some effects of fentanyl can be life-threatening.

One of the most serious risks of fentanyl patches is respiratory depression, which is when your breathing becomes dangerously slow. Too much fentanyl can cause the parts of the brain that are in charge of breathing to slow down, making it harder for your body to get enough oxygen. Respiratory depression can quickly become life-threatening.

Warning signs of respiratory depression or overdose include:

• Extreme sleepiness and trouble waking up
• Long pauses between breaths while sleeping
• Bluish lips or fingertips
• Fainting or loss of consciousness
• Seizures
• Weakness or limpness

The risk of respiratory depression is even higher in people who use fentanyl patches with other substances, such as benzodiazepines or alcohol. Mixing these substances can make breathing problems even worse. It’s important to tell your healthcare providers about all the medications and supplements you take to help prevent dangerous interactions.

Being Prepared With Naloxone

It’s a good idea to keep naloxone (Narcan) on hand if you’re at risk of overdose. Naloxone is a medication that can quickly reverse the effects of an opioid overdose. It is commonly available as a nasal spray.

However, even if you use naloxone, someone needs to call 911 right away. You still need emergency medical care.

Understanding Dependence, Treatment, and Opioid Use Disorder

Because fentanyl is a powerful opioid medication, many people worry about becoming “addicted” to their medication. However, there’s a difference between physical dependence, opioid use disorder, and appropriate medical use of opioids. Although these terms are often confused with each other, they don’t mean the same thing.

Understanding the differences can help people living with OUD and their caregivers recognize when opioid use is appropriate and when additional support may be needed.

Physical Dependence

Physical dependence is a normal response that may happen if you take an opioid medication for an extended time. This type of dependence results from your body getting used to the medication over time.

If you suddenly stop the medication, withdrawal symptoms — like pain, chills, anxiety, and diarrhea — may appear. These symptoms can happen even if you take the medication as prescribed by your doctor.

Opioid Use Disorder

If you’re unable to control your opioid use and have trouble managing your cravings for opioids, even when trying to stop using them, you may have OUD. People with OUD continue to take opioids even though it has negative effects on their health, relationships, or daily life.

Having OUD may raise your risk of overdose when using fentanyl patches. This risk can make treating a chronic pain condition more complex, especially if you’re using other substances, like benzodiazepines, at the same time.

It’s important to always use fentanyl patches only as prescribed. Talk to your healthcare provider if the patch isn’t providing enough pain relief.

Appropriate Medical Use

Many people use opioids safely under the supervision of a healthcare provider. Appropriate use of opioids includes:

• Taking the opioid exactly as prescribed
• Attending follow-up appointments regularly and contacting your healthcare provider if you have any side effects
• Using the same pharmacy for all of your medications so the pharmacist can check for dangerous drug interactions

Join the Conversation

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Have you experienced any unexpected side effects from a fentanyl patch? Let others know in the comments below.