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Effects of Fentanyl: What to Expect: (Short and Long-term)

Fentanyl is a pain reduction medication that works by blocking the body’s pain receptors in the brain and increasing dopamine within the central nervous system. Fentanyl is the strongest U.S. Food and Drug Administration (FDA) approved opioid painkiller on the market; more than 50 times stronger than morphine. It is incredibly addictive, and you may build up a tolerance quickly, even if taking as prescribed, causing you to need more of the drug to relieve pain.  

Buying and selling fentanyl on the street has become more popular over the years, and it’s perilous because of its high potency. On the street, you might hear it called China White, Apache, China Girl, or Goodfellas.

Usually, fentanyl is administered in a pill, patch, lollipop, or lozenge, but when using illegally, some people choose to snort it, inject it, smoke it, or dissolve it under their tongues. Even small overdoses can result in death. Mixing it with other illicit drugs such as cocaine or heroin is especially dangerous.

What are the Physical and Mental Effects/Impacts of Fentanyl Use?

There is nothing wrong with using fentanyl in a medical setting. It may be helpful to patients who are in chronic pain and to those who are already tolerant of other opioid treatments. It is often used for patients when no other type of pain regulation treatment has worked.

Fentanyl can also be used as an anesthetic and to manage pain associated with heart disease. Cancer patients, in particular,  use the fentanyl patch to provide continuous pain relief. When a patient is terminally ill, there is less concern about addiction and more concern about pain management. Nothing is quite as effective as fentanyl at reducing or eliminating pain.While the medication is an extremely effective drug, it can come with some side effects and undesirable impacts.

Here is a list of them:

  • Sedation
  •  Pupil constriction
  • Respiratory depression
  • Dry mouth
  • Confusion
  • Stomach problems
  • Sweating or flushing
  • Decreased heart rate
  • Stiff muscles
  • Addiction
  • Overdose
  • Accidental Death

Short-term Effects Of Fentanyl

As the most potent opioid used in the medical field, fentanyl is commonly associated with sedation. It blocks pain receptors in the brain. This can serve to reduce or eliminate pain in someone sick or undergoing surgery. It is often used for anesthetic purposes during heart-related surgery. The drug produces a euphoric feeling for people who do not need it for medical reasons.

As dopamine levels increase and the pain receptors in the brain are blocked, fentanyl dosages cause your breathing to slow down. If the drug is overused, over time, this respiratory depression will become worse and could result in accidental death. Feelings of sleepiness and confusion are common, as the drug reduces your heart rate and blood pressure to drop.

Long-Term Effects of Fentanyl

Over the long-term, fentanyl can be associated with addiction and overdose. The people who become addicted to it often begin taking it as the result of an injury or surgery. Patients start to build up a tolerance to the drug, and the body craves more and more of it to feel normal. So, they may take more.

Other times, fentanyl is used in place of cocaine or heroin or even mixed with other drugs into a “designer drug” to stretch the batch or to produce a stronger high.

Fentanyl is illegally produced in laboratories all over the country. Since this production is not associated with a medical problem, nor regulated by the federal government, it is easy for a person to overdose on street fentanyl accidentally. This version of the drug is so potent that even a small discrepancy in dosage could cause accidental death. Accidental overdose is prevalent in recreational users of the drug.

How Do Effects Differ Depending on Level and Length of Use?

Generally, fentanyl only provides pain relief for 60-90 minutes. For those in chronic pain, a doctor may prescribe a patch that will slowly release the fentanyl for a total of 36 hours. The body quickly builds up a tolerance to it, and it requires a larger dosage for you to experience pain relief or to achieve a feeling of euphoria.

Common effects of short-term use are sweating and flushing, along with stomach problems and drowsiness. Addiction and dependency may come in to play when used for the long-term. It is possible to begin feeling like something is not right if there is no dose of fentanyl. Stopping the use of this drug should always be under the supervision of a doctor and closely monitored.

Fentanyl addiction can be a very difficult cycle to break. If you have been taking it mixed in with other drugs, your body may have become dependent on it. Once dependent on the drug, you may behave very out-of-character to pursue more of it.

If you try to stop taking fentanyl cold turkey, you will more than likely experience intense withdrawal symptoms.

Are There Ways to Reverse the Effects?

When there is no longer a medical reason to take fentanyl, your doctor will probably taper the drug, reducing the dosages slowly until you are no longer dependent. He or she may write a prescription for a substitute or other medication tailored to help you come off of the drug without experiencing uncomfortable fentanyl withdrawal symptoms.

Some of those include, but are not limited to:

  • Pupil dilation
  • Vomiting
  • Diarrhea
  • Goosebumps
  • Runny nose
  • Hot and cold flashes
  • Anxiety
  • Agitation
  • Insomnia
  • Severe pain throughout the body

How Do You Reverse the Effects of Fentanyl Use?

To reverse the effects of fentanyl use, you would first need to stop taking the drug. This process should be overseen by a doctor to monitor and put you on you a taper schedule. In the case of addiction, you may require residential or outpatient treatment and a plan for withdrawal. A doctor can also prescribe medication to help with these symptoms and to reduce the cravings for fentanyl.

If you are addicted to fentanyl, know that you’re not alone and don’t have to contend with overcoming this addiction alone. If you are taking it under the direction of a doctor, keep him/her informed of the way it is making you feel and any cravings you may be having.

You might also want to consider attending a treatment program so you can undergo supervision through the detox phase. It’s helpful to have a strong support system during detox and the early stages of treatment. Whether you decide to stay at a residential treatment center or commute to an outpatient center, know that professionals are available to assist you.  You don’t have to navigate recovery efforts on your own.

Give us a call today and allow us to assist you. Your first step toward recovery is to reach out for help. We’re here, and we care.


NIDA. (2019, February 28). Fentanyl. Retrieved from

U.S. National Library of Medicine. Fentanyl. Retrieved from

U.S. Drug Enforcement Administration. Fentanyl. Retrieved from

Medical NewsToday. (2019, September 2) What to know about opiate withdrawal. What are the symptoms of opiate withdrawal? Sissons, B., Westphen, D. PharmD. Retrieved from

Medline Plus. Fentanyl. Retrieved from

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