Fentanyl Addiction & Treatment: Effects, Signs, & Symptoms
Last Updated: November 2, 2023
Opioids have a long history of medical and recreational use. Advances in the ability of pharmaceutical companies to synthesize and distribute huge quantities of legal opioids have significantly contributed to the opioid epidemic that has devastated parts of America in recent years. Fentanyl is a potent opioid that has been a significant factor in the rise in opioid-related deaths in the U.S.
What is Fentanyl?
Fentanyl is a prescription opioid that is in the same class of drugs as morphine, codeine, hydrocodone and oxycodone (OxyContin, Percocet), but it is up to 100 times more potent than morphine and 50 times more potent than the illegal opioid heroin. Many prescription opioids are semi-synthetic drugs, meaning that they are derived from natural opiates like morphine, but fentanyl is a fully synthetic drug that is created in pharmaceutical labs. Its potency also contributes to its addictiveness and lethality.
Fentanyl analogs are derived from fentanyl but have slight modifications to the chemical structure. Many of these analogs are far more potent (and lethal) than fentanyl. For example, carfentanil is 100 times more potent than fentanyl and is used by veterinarians as an elephant tranquilizer. In recent years, carfentanil has been identified in confiscated drugs and in people who died from opioid-related overdoses.
Signs & Symptoms
Fentanyl abuse is associated with some characteristic signs that can help people determine whether someone they know is using it.
Side effects include:
- Drowsiness or stupor
- Muscle flaccidity
- Cold, clammy skin
- Poor motor coordination
- Constricted pupils
- Reduced breathing and/or heart rate
People abuse fentanyl for its ability to produce a temporary euphoria, but they also experience unwanted symptoms, including:
- Dry mouth
- Inability to concentrate
- Trouble breathing
- Chest pain
Withdrawal & Detox Process
Fentanyl withdrawal is a profoundly uncomfortable process, especially for people who quit without medical support. Medical detox programs are the safest and most effective way to quit taking fentanyl or any other opioid. In addition to around-the-clock supervision by addiction specialists, medical detox programs can provide a dose tapering schedule and medications that will substantially ease withdrawal symptom severity and reduce the duration of withdrawal.
The fentanyl withdrawal and detox process is somewhat different for each person who goes through it, but a very general timeline can be described:
- 2-4 hours: Withdrawal symptoms begin
- 1-3 days: Peak symptom severity
- 3-10 days: Symptoms will gradually resolve
Physical withdrawal symptoms:
- Runny nose
- Watery eyes
- Muscle cramps
Psychological withdrawal symptoms:
- Dysphoria (a feeling of unease or dissatisfaction)
- Anhedonia (an inability to experience pleasure)
There are several factors that influence the withdrawal process, including:
- Frequency of use
- Route of administration
- Polydrug abuse (abuse of fentanyl with other drugs or alcohol)
- Genetic profile
- Physical and mental health status
Some people experience protracted withdrawal symptoms that persist for weeks or months after they quit. This is called post-acute withdrawal syndrome (PAWS) and it is frustratingly common in people recovering from opioid use disorders. Over time, these symptoms will gradually lessen in intensity. Some people require additional long-term treatment in the form of medication-assisted treatment (MAT), which replaces opioids of abuse with opioids that are not associated with an addiction-reinforcing high. MAT can help people struggling with protracted withdrawal overcome their symptoms.
A fentanyl overdose can quickly become lethal. Fentanyl slows activity in parts of the brain that are responsible for maintaining proper breathing and heart rate, and too much fentanyl can cause respiratory depression (shallow, irregular breathing) that can lead to a coma or death. Mixing fentanyl with alcohol, other opioids or benzodiazepines is very dangerous. Combining drugs that slow brain function (as all of these do) leads to a synergistic effect; in other words, the combined effect of the drug combination is more than would be expected based on the effect of any of the drugs taken alone. The majority of opioid-related overdose deaths also involved alcohol or other drugs.
Fentanyl is a drug that has unique challenges for people who want to quit, and professional rehab is often an important component of successful long-term recovery. Because this drug is so addictive, many people participate in a comprehensive residential rehab program before transitioning to an outpatient program.
Rehab programs for fentanyl treatment include:
- Medical detox: Medical detox programs include 24/7 supervision by medical professionals who can intervene in the case of complications and, when appropriate, provide medications to help people manage fentanyl withdrawal symptoms
- Residential Rehab: The first days and weeks of recovery are the most difficult. Residential rehab programs give clients a chance to achieve early success without the risk of encountering triggers or succumbing to temptation
- Outpatient Rehab: For people with fentanyl use disorders, outpatient rehab generally follows a residential program. Many rehab facilities offer a range of outpatient programs including intensive outpatient and partial hospitalization to support clients in many stages of recovery
- Aftercare: Recovery is often a lifelong pursuit. Aftercare programs give people in recovery a way to meet new people and learn new hobbies in a safe environment
While there are no shortcuts through the withdrawal and recovery process, there are some medications that can make it easier. Acute withdrawal symptoms can be incredibly challenging to endure, and long-acting benzodiazepines may be prescribed to help reduce symptom severity.
Opioids, including fentanyl, create long-term changes in brain chemistry. Some people experience debilitating withdrawal symptoms months or even years after they quit. For these people, medication-assisted treatment (MAT) may be appropriate. MAT is an opioid-replacement therapy that takes advantage of drugs that are chemically similar to opioids of abuse but that does not cause the euphoric high that opioids are known for. These drugs mimic opioids of abuse in the brain but without reinforcing addiction or promoting abuse.
Some people claim that MAT simply trades one addictive drug for another, but they misunderstand the theory underlying opioid replacement strategies. MAT is a way to manage a physical dependence, not a way to perpetuate an addiction. People who are physically dependent on opioids experience debilitating withdrawal symptoms when they don’t take the drugs, which increases their risk for relapse and adverse health and social consequences. MAT can give people a real chance at achieving a healthy, productive lifestyle, and some MAT patients choose to stay on the drugs long-term.
Related Topic: Inpatient vs. Outpatient Rehab
Other frequently asked questions about fentanyl include:
Is fentanyl an opioid?
Yes, fentanyl is an opioid. However, unlike many other commonly prescribed opioids, fentanyl is a fully synthetic opioid, meaning that it is made in a lab. Semi-synthetic opioids like oxycodone and heroin are modified versions of natural compounds that are derived from opium poppies. Synthetic opioids are among the most potent (and dangerous) opioids.
How long does fentanyl stay in your system?
The amount of time that a drug stays in your system is based on the drug’s half-life, which is the amount of time it takes for half of the drug to be metabolized. For example, if someone took one milligram of a drug with a five-hour half-life, they would have 0.5 milligrams left in their body five hours later. In another five hours, they would have 0.25 milligrams remaining. As a general rule of thumb, a drug will be out of your system in approximately five half-lives.
The half-life of fentanyl varies based on how the drug is taken, but the average half-life is about seven hours. Consequently, fentanyl can be detected in your system for about 35 hours. Transdermal fentanyl patches slowly administer fentanyl through the skin and have a much longer half-life, around 20-27 hours.
How much fentanyl is lethal?
Fentanyl has been a key driver of opioid-related deaths in recent years. Fentanyl is about 50 times more potent than heroin and up to 100 times more potent than morphine, and a fentanyl dose the size of a few grains of sand (about 3 milligrams) could kill an adult man. By some estimates, as little as 250 micrograms could be a fatal dose.
Fentanyl tolerance develops rapidly, so people who regularly use fentanyl can tolerate larger doses without risking their lives. However, a key risk for these people is using fentanyl after a few days off of it. If their tolerance drops (often because they were jailed or hospitalized) and they take their normal dose, they are at increased risk for serious complications or death caused by an overdose.
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