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Fentanyl Laced Weed: Signs and Effects of Fentanyl Overdose

Last Updated: March 20, 2024

Authored by Sharon Levy, MD, MPH

Reviewed by Michael Espelin APRN

Fentanyl(fentanil) is a medication used in the treatment of pain. It is many times more potent than morphine. Because of this, even small amounts of this medication present the risk of overdose.

However, it’s frequently abused on its own and is sometimes added to increase the addictive potential of other drugs. There are many dangers around such laced drugs. This article will discuss fentanyl-laced weed and other drugs, as well as the dangers of a fentanyl overdose.

Fentanyl-Laced Weed

Marijuana is a drug that is now legal or decriminalized in many parts of the world. Even in places where it still happens to be illegal, many see it as a soft recreational drug.

However, despite this, fentanyl in weed is a dangerous practice done to increase its potency and addiction potential. It can present a lot of danger to the person using the drug. This is an actual problem. There is no abundance of statistics specifically underlying how rampant this issue is. Still, numerous documented cases in the news show that this is indeed a practice for marijuana sold on the streets.

Dealer selling marijuana in the street.

In the United States, a news story talked of two teens found dead after smoking fentanyl-laced weed. They were unaware of this, resulting in them overdosing on the drug’s content in the marijuana.

In April of 2019, marijuana was seized in the parking lot of a shopping center. When it was tested, it was found to contain Fentanyl. In this case, it was confiscated before it could cause any harm, but this is not the case for many. Fentanyl deaths have been on the rise, which is linked to an increase in its use to adulterate other drugs.

Fentanyl-Laced Weed Side Effects

Whether it’s taken accidentally or intentionally, there are some effects that it can have on the user’s health. Someone who smokes fentanyl-laced weed, for instance, will feel these same effects.

These Side Effects Are Similar to Those Of Most Opioids, and They Include:

  • Reduced breathing
  • Slowed heart rate
  • Drowsiness
  • Confusion
  • Inattention
  • Constricted pupils
  • Lethargy
  • Nausea
  • Constipation
  • Dry mouth
  • Excessive sweating

Other Dangers

Apart from those side effects that a user can feel immediately after taking the drug, there are other dangers that an individual is at risk of. These include overdose and dependence. These can occur from unknowingly consuming fentanyl in weed or other drugs.

Girl smoking fentanyl-laced weed.

It is up to 100 times more potent than morphine, so it is evident that even a small dose of it in fentanyl-laced weed can cause an overdose. Unfortunately, when these drugs are laced with fentanyl, they are not done with regard to any exact measurements or dosages. As a result, an overdose is a frequent occurrence. Similar to overdose on any opioid, it can potentially be fatal.

Dependence is another major problem. If the individual does not overdose, they may begin to crave the effects of the drug, unaware that it was laced. If they suspect that those effects were due to this medication, they may start abusing it on its own and develop an addiction. This can have several effects on the individual’s health and can eventually result in overdose due to its potency.

Other Drugs Laced with Fentanyl

Marijuana is not the only drug that frequently gets laced. This often happens with drugs such as heroin and cocaine and even prescription pills like Xanax.

In 2014 alone, a Canadian police department found that about 25% of all overdose deaths in the province were related to drugs that had been laced with this medication.

In one county in the United States, 2019 saw 152 deaths related to overdoses, and in the first half of the second year, 203 of these were fentanyl deaths. These deaths were suspected to be due to drugs laced with this medication mostly. This clearly shows how this problem is gaining momentum.

Magifying glass checking counterfeit pills.

The primary motivation behind for those who manufacture these drugs is to give a more intense effect and to increase the addictive potential of the drug. Getting users hooked is more business for those who traffic and produce these substances.

Unfortunately, individuals who use these drugs are most times completely unaware that the drug is laced. As a result, they may decide to take more of the drug than they usually do, thinking it might be safe. This can result in overdose, which, when unattended to, can be fatal.

Fentanyl in Cocaine

Cocaine is an illicit drug with stimulant properties. In San Francisco, three individuals presented to an emergency room following a fentanyl overdose from what they believed to be cocaine. It was ultimately fatal for one of these people.

In 2016 in New York City, excluding heroin, 37% of overdose deaths had laced cocaine implicated. It was in stark contrast to 11% that it was in the previous year. Moreover, one study found that the increase in deaths that seemed to be related to cocaine overdose implicated fentanyl as the main factor. This drug can frequently be used in amounts larger than intended, and that makes overdose on cocaine cut with this drug very likely to occur.

Fentanyl in Heroin

Heroin is also an opioid. However, it is not as potent. As a result, it adds a more intense effect to heroin and increases the addictive potential of a drug that is already notorious for its addiction problem.

A study found that most heroin users could not determine whether their heroin was laced with this medication. However, most of these users were tested and found to have had exposure to the drug.

Heroin is a drug that is usually injected by those who abuse it. The large gap in potency between fentanyl and heroin means that those who use the former intravenously with the notion that it is heroin can easily overdose on the drug. In most cases, the effects can be nearly instant.

Fentanyl Laced Xanax

Xanax is a prescription medication that is used for the treatment of anxiety disorders. Many people use it to feel more relaxed, and its abuse is particularly abundant amongst young adults and adolescents.

In 2019, a University of Arizona student died following a fentanyl overdose when taking what he was made to think was purely Xanax. One county in Delaware recorded multiple overdoses and deaths related to Xanax that was cut with this drug. Unfortunately, this widespread problem can result in this drug which they believe to be relatively harmless, resulting in their deaths.

Man buying drugs in the street.

In general, as long as a drug is being bought on the street, a user can never be sure about the purity of the drug’s contents. It just emphasizes why these drugs should be avoided and treatment sought. Even marijuana becomes potentially fatal since users never know if they are getting fentanyl-laced weed.

Fentanyl Test Strips

In cases where it’s impossible to be sure about the contents of a certain drug, fentanyl test strips can be used. One study gave these strips to multiple drug users and found that 50% of them who used the strips reported at least one positive result.

Using fentanyl test strips has benefits like specificity for fentanyl and analogs like ocfentanil. Additionally, its accuracy is put at 98%, and the time to results is given as 5 minutes. The test result is easy to read, with one red line depicting its presence and two red lines, even if faint, representing its absence.

This intervention can make drug use safer for those who may find it hard to quit the habit at the time.

Lethal Dose of Fentanyl

The lethal dose of fentanyl comes in at just 2mg, which is a minuscule amount. In contrast, the lethal dose of heroin is 200mg, which is the same on average for morphine. When the drug is substituted in these drugs, the tiniest amount is capable of producing overdose. However, most addicts will still use the quantity that they typically do.

Carfentanil is one of fentanyl analogs, and it is 100 times more potent. Considering the potency, it’s clear that the tiniest amount of carfentanil can cause an overdose. This is a drug used to tranquilize large animals like elephants due to its potency. However, it is sometimes cut into illicit drugs. The current lethal dose of this drug is unknown in humans but is suspected to be around 20µg based on the lethal dose in animal studies. Compared to the lethal dose of fentanyl, this quantity will be challenging to measure without sophisticated equipment, increasing its danger.

Another important issue is mixing the drug with alcohol. This combination can speed up and intensify the drug’s effects. The fatal dose of the medicine can vary. It depends on other drugs taken, a person’s height, weight, age, and physical condition.

Other Fentanyl Overdose Causes

When it is mixed with other drugs such as heroin or cocaine, it can result in an overdose, as stated earlier. However, this is not the only case in which an overdose can occur.

It is not safe to think that just because a doctor prescribed this medication, one can take it free from the dangers of overdose. Different things can affect the way it works in the body. That is why it’s important to be closely monitored by the doctor while taking this medication to prevent any side effects. Doctors are also aware of the risks, so it should only be prescribed to patients who are tolerant to weaker opiates but suffer from severe and chronic pain. One should also know how long fentanyl stays in the system, to be sure not to take more than the body can handle.

Doctor writing a prescription.

If one is using a fentanyl patch, one should be aware that temperature affects the drug’s levels released by the patch. Large amounts of heat, such as being in contact with a heating mat, cause the patch to release more of this drug which can cause an overdose.

Fentanyl Overdose Signs

This drug is a very potent opioid. It can do severe damage to almost every organ in the human body.

Some Of the Most Common Fentanyl Overdose Signs Are:

  • Slowed breathing
  • Low blood pressure
  • Low heart rate
  • Pale face
  • Confusion
  • Dizziness
  • Problems with speech
  • Thinking problems
  • Nausea
  • Vomiting
  • Purple lips and fingernails
  • Constricted pupils
  • Seizures
  • Coma
  • Death

Overdose is even possible if a doctor prescribed the medication. That is one of the reasons why doctors closely track patients who use this drug.

If any of the fentanyl overdose signs listed above are noticed, it is imperative to call 911 immediately. This is because fentanyl overdose can have a fatal result.

Fentanyl Overdose Effects On Body and Brain

Like other opioids, the drug binds to opioid receptors in our brain. As a result, it induces the feeling of relaxation and euphoria. Opioid receptors are very close to the center of the brain that controls breathing. Therefore, higher doses of this drug can cause breathing problems. Consequently, this deprives the body of precious oxygen. Ultimately, this can result in severe health effects, such as serious organ damage or death. A prolonged lack of oxygen can lead to permanent brain damage. This is called hypoxia.

Almost 90% of patients who suffer from a fentanyl overdose will never fully recover. Therefore, this leads us to the conclusion that the long-term effects of this drug are quite severe.

Fentanyl Overdose Response

If an individual suspects an overdose by noticing fentanyl overdose signs in someone around them or at home, they must respond promptly to avoid fatal consequences.

  • The first and most crucial step is to contact emergency services and call 911. It is integral to inform emergency services as early as possible. Following this, you can begin first aid.
  • If it occurs in an area where naloxone, also known as Narcan, is available, it should be administered promptly. It acts as an antidote to opioid overdoses. It may be a nasal spray or an injectable solution. Either way, make sure to read the instructions and follow them for administration. Breathing can take up to five minutes to normalize, and some people may need a second dose after two to three minutes.
  • If breathing ceases, which is likely with an opioid overdose, CPR should be commenced.
  • The person should be monitored until emergency services arrive at home.

Fentanyl is an extremely potent medication that can cause an overdose in minimal amounts compared to other illicit substances. Unfortunately, most drug users don’t know the contents of the drugs they consume and can inadvertently overdose on marijuana laced with fentanyl or an array of other drugs that have the opioid added. The lethal dose of fentanyl is tiny, so this can potentially be fatal.

The definitive way to remove this risk is to get treatment for drug use problems. It can be done by registering at any drug treatment center. Drug cessation causes fentanyl withdrawal, which is best handled at a rehabilitation facility. It is never too late to get better.

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Published on: March 17th, 2017

Updated on: March 20th, 2024

About Author

Sharon Levy, MD, MPH

After successful graduation from Boston University, MA, Sharon gained a Master’s degree in Public Health. Since then, Sharon devoted herself entirely to the medical niche. Sharon Levy is also a certified addiction recovery coach.

Medically Reviewed by

Michael Espelin APRN

8 years of nursing experience in wide variety of behavioral and addition settings that include adult inpatient and outpatient mental health services with substance use disorders, and geriatric long-term care and hospice care.  He has a particular interest in psychopharmacology, nutritional psychiatry, and alternative treatment options involving particular vitamins, dietary supplements, and administering auricular acupuncture.

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