Six Fentanyl Side Effects: Understanding the Short-Term & Long-Term Risks

What was once considered a rarity among drug users due to its strictly controlled availability, fentanyl has become the most popular opioid on the street market. As the overprescription of pain pills was regulated by the FDA, heroin, and then fentanyl, surged to fill the demand - sponsored largely by the illicit manufacturing by criminal organizations. The result - using fentanyl has become commonplace; even amongst adolescents and young adults. Because of this increased use, it’s imperative that the public is aware of the long and short-term risks of fentanyl use. 

Short-Term Side Effects

Respiratory Depression:

Using fentanyl depresses the central nervous system which in turn causes breathing to become slow and shallow. Breathing that is slowed down and restricted can cause insufficient oxygen levels in the blood which can lead to brain damage and death. 

Nausea & Vomiting:

Fentanyl addiction can trigger a part of the brain responsible for detecting chemicals in the blood which should not be there. When high levels of fentanyl are detected, a response is sent to the brain triggering nausea and vomiting. It’s the same physical reaction that occurs when cancer patients get sick after chemo treatment. 

Drowsiness & Confusion:

Along with breathing, the depression of the central nervous system due to the ingestion of fentanyl, negatively affects cognition and consciousness. Taking doses of fentanyl can cause severe drowsiness and impair cognitive abilities. This drowsiness and impairment is colloquially known as “nodding” and is actively sought out by users. Nodding has a small margin of error and can quickly turn into an overdose if too much fentanyl is taken.  


Long-Term Side Effects

Physical Dependence:

If taken consistently over a long period of time (weeks) fentanyl will produce a physical dependence. The body becomes accustomed to the presence of the drug and the flood of neurotransmitters it produces. Fentanyl is so good at producing dopamine and serotonin that the brain begins to shut off its own production of these critical chemicals. If fentanyl use is stopped or reduced, the body will experience severe withdrawal symptoms.


As the physical dependence grows, the body requires more and more fentanyl to achieve the desired results. Without the increased amounts of fentanyl, the body gets sick and goes into fentanyl withdrawal. Increased the amount of fentanyl being consumed daily means an increase in spending to procure fentanyl. Increasing tolerance is one of the fastest ways to financial ruin. It should be noted that there is no cap on how high one's tolerance can go. As long as you continue to take more fentanyl, the tolerance will continue to rise. 


Physical dependence and an increasing tolerance are hallmarks of fentanyl addiction. Once addicted to fentanyl, it is very difficult to stop unless you seek professional treatment. It’s also a very easy way to die. Over 80,000 people died in 2021 from opioids. Fentanyl’s potency makes every use a gamble. If it doesn’t kill you, it will take everything from you - health, wealth, well-being, and every material possession and relationship you cherish. 

Risk Prevention

The easiest way to stop the risks of fentanyl is abstinence. If you’ve never used fentanyl, don’t. If you’re actively caught up in fentanyl addiction, seek professional fentanyl treatment to detox. Prescribed fentanyl by a doctor? Use only as prescribed and very cautiously. Talk with your doctor about any concerns you may have. Avoid mixing fentanyl with alcohol or any other drugs. The potency of fentanyl can be exacerbated by these other drugs, increasing the chances of overdose and death. Keep Narcan around in the case of an overdose. 

Ready to quit gambling with your life and get off fentanyl once and for all? Call Sunflower Recovery today to talk with our experienced team about your options. We’ve worked with countless fentanyl users and helped them get off the dope and onto the path of recovery. 

How Fentanyl Affects the Mind & Body