Fentanyl Withdrawal Symptoms, Treatment & Detox in Kansas City

Fentanyl is a highly potent synthetic opioid that has a high risk of addiction and potentially fatal overdose.1 Fentanyl withdrawal can be extremely uncomfortable and, although not typically life-threatening, could be dangerous in some cases due to complications or relapse, especially if a person does not receive medical assistance.2

If you or a loved one uses fentanyl or other opioids, you should understand your treatment options. Fentanyl detox can help you safely undergo withdrawal and start the path to recovery.

What Is Fentanyl Withdrawal?

Fentanyl withdrawal occurs due to physical dependence, meaning that a person needs to take the drug to prevent withdrawal symptoms. Over time, more of the drug is needed for the same effect. When a person who is dependent stops using fentanyl, they can develop fentanyl withdrawal symptoms due to the absence of the drug.2

What Causes Fentanyl Withdrawal?

As mentioned above, fentanyl withdrawal refers to the range of symptoms that occur when someone who is physically dependent on fentanyl suddenly reduces their dose or stops using it.2 Fentanyl binds strongly to the brain’s opioid receptors, which regulate pain and reward.3 Because it is much stronger than heroin, with even microgram doses having the potential to significantly change a person’s brain chemistry, the body quickly adapts to its presence.3,4

Over time, a person can develop tolerance, requiring more of the drug to feel the same effects. They may also develop a dependence, which means they need to take the drug to function normally.4 When someone suddenly stops using fentanyl, the receptors struggle to adapt again without the presence of the drug, resulting in highly uncomfortable withdrawal symptoms.2

Symptoms of Fentanyl Withdrawal

Fentanyl withdrawal can cause a wide range of symptoms that affect a person’s body and mind; these symptoms can vary in intensity and risk based on individual factors.1 Although symptoms are not usually life-threatening, they can be extremely intense and uncomfortable, which could also increase the risk of relapse.2 Withdrawal symptoms fall into physical and psychological categories.

Fentanyl Physical Withdrawal Symptoms

Physical symptoms of fentanyl withdrawal can be highly uncomfortable. They may include:5

• Bone pain
• Muscle aches and tension
• Changes in body temperature
• Chills and goosebumps
• Heightened sensitivity to pain
• Insomnia
• Eye tearing
• Droopy eyelids
• Dilated pupils
• Stomach cramps
• Nausea
• Vomiting
• Diarrhea
• Rapid heartbeat
• Arrhythmias
• High blood pressure
• Teeth chattering
• Weakness
• Yawning

Fentanyl Psychological Symptoms

Fentanyl withdrawal can also adversely affect a person’s mental health. The psychological symptoms of fentanyl withdrawal may include:5, 6

• Emotional difficulties
• Anxiety
• Low mood
• Irritability
• Loss of motivation
• Malaise
• Stress

One study indicates that stopping long-term prescription opioid use placed people at a greater risk of suicide or self-harm.7 Additionally, people with underlying depression or anxiety should receive treatment for these conditions to prevent complications, other risks, and relapse. It’s important to note that opioid withdrawal is not generally life-threatening, but people should seek immediate assistance and call 911 right away if they experience suicidal ideation.2

How Long Does Fentanyl Withdrawal Last?

The fentanyl detox timeline can vary by individual factors, such as a person’s health, frequency of use, and other concurrent substance use.8

How long does fentanyl withdrawal last? As with heroin, fentanyl is a short-acting opioid, so symptoms typically begin 6-12 hours after the last dose.6, 9 Therefore, heroin vs fentanyl withdrawal tends to be similar in symptomatology.6

In general, the withdrawal timeline follows an arc, which can involve the following phases:6

• Early withdrawal (which generally starts 6-12 hours after a person’s last dose): People may start to experience initial symptoms, which can include anxiety, cravings, depression, and sweating.
• Peak withdrawal (1-3 days later): This phase can involve an increase in symptom intensity, such as more anxiety, abdominal cramping, vomiting, and cravings.
• Resolution (after 5-7 days): Symptoms often begin to resolve but can last longer for some people.

Some people may develop protracted withdrawal, which can involve longer-term withdrawal symptoms that last weeks or months.6

Protracted Fentanyl Withdrawal (PAWS)

Post-acute withdrawal syndrome (PAWS), also known as protracted withdrawal, involves less acute withdrawal symptoms that last beyond the typical withdrawal timeline. These symptoms can involve anxiety, low mood or depression, an inability to experience pleasure, and insomnia for weeks or months following withdrawal.6,10 One study indicates that around 90% of people in recovery from opioid dependence experience some form of PAWS.10

There is no clear cause of PAWS, but research hypothesizes that it could occur due to factors like neuroadaptations, nutritional deficiencies, stress, or potentially undiagnosed mental health disorders that negatively affect the body’s ability to function on an optimal level.10

Is Fentanyl Withdrawal Dangerous?

Fentanyl withdrawal is not typically dangerous or life-threatening in and of itself.2 However, withdrawal complications can be potentially harmful, especially when a person does not receive proper medical treatment and supervision. In particular, research indicates that diarrhea and vomiting may lead to dehydration, a type of electrolyte imbalance known as hypernatraemia (elevated blood sodium level), and resultant heart failure.11

People who experience more severe withdrawal symptoms can also have a higher risk of anxiety and depressive symptoms, so it is also important to be aware of potential mental health risks.8 One of the biggest risks of detoxing or quitting for a short period of time is reduced tolerance, which can increase the risk of potentially fatal overdose, as people can overdose on a much smaller dose than they are used to. 2

Medical Detox for Fentanyl Withdrawal

Fentanyl withdrawal treatment and detox involve a set of interventions designed to minimize the harm caused by substance misuse.12 Medically supervised detox can help keep people as safe and comfortable as possible as they undergo withdrawal from opioids like fentanyl and can also help reduce the risk of relapse when combined with a long-term treatment plan.12,13

Opioid detox programs on an inpatient or hospital-based level can involve 24/7 support, supervision, and the provision of detox medications, such as methadone or buprenorphine to minimize withdrawal symptoms that ensure a person’s comfort.13 It is important to note that medically-supervised withdrawal is different from medication-assisted treatment (MAT), which can take place following the completion of withdrawal and involves ongoing medications and psychosocial support to help people maintain post-detox recovery.14

Fentanyl Detox & Addiction Treatment in Kansas City

Detox is often the first step in the recovery process, but it is typically not enough to help people maintain long-term abstinence. Formal treatment is advised so that people can learn necessary skills and address underlying issues to support their ongoing recovery.13

Empowered Recovery Center in Kansas City offers flexible rehab programs that provide evidence-based therapies and individualized treatment plans to suit all needs. We can help you start your recovery from fentanyl misuse. Please call us to learn more about the rehab admissions process for substance abuse treatment in Kansas City, rehab insurance coverage, paying for rehab, and verifying your insurance benefits.

References

1. Luba, R., MacLean, R. R., & McCann, D. J. (2023). Fentanyl withdrawal: Understanding symptom severity and the influence of body mass index. Frontiers in Psychiatry. Retrieved September 22, 2025, from https://pmc.ncbi.nlm.nih.gov/articles/PMC9992259/
2. National Library of Medicine. (2024, May 4). Opiate and opioid withdrawal. MedlinePlus Medical Encyclopedia. U.S. Department of Health & Human Services. Retrieved September 22, 2025, from https://medlineplus.gov/ency/article/000949.htm
3. Vo, Q. N., Mahinthichaichan, P., Shen, J., Ellis, C. R., et al. (2021). How μ-opioid receptor recognizes fentanyl. Nature Communications. Retrieved September 22, 2025, from https://www.nature.com/articles/s41467-021-21262-9
4. National Institute on Drug Abuse. (2025, June 6). Fentanyl: Overdose & addiction crisis. NIDA. Retrieved September 22, 2025, from https://nida.nih.gov/research-topics/fentanyl#overdose-and-addiction-crisis
5. Pergolizzi, J. V. Jr., Raffa, R. B., & Rosenblatt, M. H. (2020). Opioid withdrawal symptoms, a consequence of chronic opioid use and opioid use disorder: Current understanding and approaches to management. Journal of Clinical Pharmacy and Therapeutics. Retrieved September 22, 2025, from https://onlinelibrary.wiley.com/doi/full/10.1111/jcpt.13114
6. American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). American Psychiatric Publishing. Retrieved September 22, 2025, from https://drive.google.com/file/d/1GbqMlAz3iDP8J52B2tnZNelpg3u-Ry6i/view?usp=sharing.
7. Oliva, E. M., Bowe, T., Manhapra, A., Kertesz, S., Hah, J. M., Henderson, P., et al. (2020). Associations between stopping prescriptions for opioids, length of opioid treatment, and overdose or suicide deaths in US veterans: Observational evaluation. BMJ. Retrieved September 22, 2025, from https://www.bmj.com/content/368/bmj.m283
8. Rodríguez-Espinosa, S., Coloma-Carmona, A., Pérez-Carbonell, A., Román-Quiles, J. F., & Carballo, J. L. (2021). Clinical and psychological factors associated with interdose opioid withdrawal in chronic pain population. Journal of Substance Abuse Treatment. Retrieved September 22, 2025, from https://doi.org/10.1016/j.jsat.2021.108386
9. Saxon, A. J. (2024). Short-Acting, Full Agonist Opioids During Initiation of Opioid Agonist Treatment in the Fentanyl Era. JAMA Network Open. Retrieved September 22, 2025, from https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2818732
10. Alsheikh, M. Y. (2021). Post-acute withdrawal syndrome: The major cause of relapse among psychoactive substances addicted users. Archives of Pharmacy Practice. Retrieved September 22, 2025, from https://archivepp.com/storage/files/article/56a855e5-b892-4d92-8143-1c686ee422b4-hLnSdOfyGNnpEBpl/archiveapp-vol12-iss4-91-97-1285.pdf
11. Darke, S., Larney, S., & Farrell, M. (2016). Yes, people can die from opiate withdrawal. Addiction. Retrieved September 22, 2025, from https://onlinelibrary.wiley.com/doi/pdf/10.1111/add.13512
12. Substance Abuse and Mental Health Services Administration. (2006). Detoxification and substance abuse treatment: Quick guide for clinicians (based on TIP 45). U.S. Department of Health and Human Services. Retrieved September 22, 2025, from https://nida.nih.gov/sites/default/files/samhsa_detoxification_and_substance_abuse_treatment.pdf
13. Providers Clinical Support System. (2021, June 11). Medically Supervised Withdrawal (Detoxification) from Opioids. PCSS. Retrieved September 22, 2025, from https://pcssnow.org/courses/detoxification-from-opioids/
14. Deyo-Svendsen, M., Cabrera Svendsen, M., Walker, J., Hodges, A., Oldfather, R., & Mansukhani, M. P. (2020). Medication-Assisted Treatment for Opioid Use Disorder in a Rural Family Medicine Practice. Journal of Primary Care & Community Health. Retrieved September 22, 2025, from https://pmc.ncbi.nlm.nih.gov/articles/PMC7278292/