Knowing what fentanyl does to your body and how fentanyl affects the body are extremely important topics of discussion, particularly as illicit fentanyl use is on the rise in the U.S., leading to overdoses and death.

Understanding fentanyl intended clinical uses can provide more details on what fentanyl does to your body.

Prescription Fentanyl

Fentanyl is an incredibly powerful opiate painkiller. In fact, it’s one of the strongest available, and it’s classified as a Schedule II drug in the U.S. This means that there is a potential for abuse with fentanyl, and when a doctor is going to prescribe it, it has to be done so carefully, with prior patient screening.

There are a few medical uses for fentanyl that are approved: for severe pain, cancer pain and pain related to surgical procedures.

Fentanyl can relieve surgical pain when people have certain heart operations or have poor heart function.

Additionally, fentanyl can also be prescribed for the treatment of severe pain relating to cancer. It’s well-suited for use in people who have around-the-clock pain and need stronger opioid medications than morphine. It can also be used in patients with severe pain or cancer pain who are resistant to other opioids.

There are extended-release fentanyl products that can provide powerful pain relief over a more extended period of time. These are available as oral lollipops and as patches. Fentanyl can also be administered as a film that dissolves under the tongue, and in a hospital setting, it can be injected.

While there are some medical uses for the drug, abusing fentanyl is dangerous and often deadly. When it’s prescribed and given in a medical setting, it’s done so very carefully and under strict supervision, based on rigid dosing guidelines.

What Happens When You Take Fentanyl

What fentanyl does to your body and how fentanyl affects the body are directly related to the fact that it’s an opioid. It impacts the brain’s opioid receptors, which is how it’s able to change the way your body feels and experiences pain.

When you take higher doses of fentanyl than therapeutically recommended, or if you abuse the drug in any way, you may experience a rush of euphoria when it’s taken. Fentanyl can also create a sense of extreme relaxation or drowsiness.

What fentanyl does to your body is based on the fact that it activates the brain’s opioid receptors. Fentanyl decreases how pain messages are transmitted throughout the body in the spinal cord, and it also changes how messages from the central nervous system are relayed. It replicates the impact of natural opioids found in your body, but in a much more profound way.

Along with relieving pain, other ways fentanyl affects the body include slowing down breathing and the respiratory system.

Some of the other ways fentanyl affects the body, particularly when it’s abused or used other than how it’s prescribed, include:

  • Dizziness
  • Urine retention
  • Dry mouth
  • Constipation
  • Itching or hives
  • Nausea
  • Vomiting
  • Appetite loss
  • Weight loss
  • Headache
  • Vision problems
  • Depression
  • Bad dreams
  • Hallucinations
  • Sleep problems
  • Sweating
  • Shaking
  • Swollen arms and legs

What Fentanyl Does to Your Body in the Long-Term

Along with considering what fentanyl does to your body in the short-term, what about the long-term?

First and foremost, long-term fentanyl use affects the body by developing addiction and dependence. When someone uses fentanyl for longer than they’re supposed to, or they abuse it, it can quickly lead to tolerance. Tolerance is one of the primary ways fentanyl affects the body.

With tolerance, your body and brain become so used to the presence of fentanyl that you need higher doses to achieve the same effect or high. Then, if you don’t use fentanyl or stop suddenly, you can experience withdrawal symptoms.

Tolerance can lead to addiction and increased drug-seeking behaviors, and it is a common and dangerous indicator of what fentanyl does to your body.

The risk of tolerance and addiction is somewhat reduced when fentanyl is taken at certain doses and used as prescribed in a controlled setting.

When you develop a tolerance to fentanyl and use increasingly larger doses of the drug, it can also lead to an overdose with symptoms including slowed respiration, coma or death. Although these aren’t the only aspects that show what fentanyl does to your body and how fentanyl affects the body, they are some of the most significant and common.

If you or someone you know is misusing fentanyl or other opioids, help is available. With proper medical detox and treatment, you can heal from the negative effects of fentanyl use. Treatment centers like The Recovery Village can help you recover from opioid addiction. Call today to learn more about treatment options.

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Editor – Camille Renzoni
Cami Renzoni is a creative writer and editor for The Recovery Village. As an advocate for behavioral health, Cami is certified in mental health first aid and encourages people who face substance use disorders to ask for the help they deserve. Read more
Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.