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About fentanyl

Fentanyl is a very potent opioid pain reliever. A few grains can be enough to kill you.

Fentanyl is usually used in a hospital setting. A doctor can also prescribe it to help control severe pain.

For medical purposes, you may take prescribed fentanyl in the form of:

  • tablets
  • injections
  • skin patches

In non-medical situations, you will experience a quick rush of well-being (euphoria) when fentanyl is injected, smoked, snorted or ingested in high doses. Euphoria is followed by a period of calm lasting 1 to 2 hours.

Misuse of patches may also produce this effect.

Reports indicate that the euphoria from fentanyl is less than with heroin or morphine.

Fentanyl enters the Canadian illegal drug market in 3 ways:

  • illegal import from other countries
  • product from illegal laboratories in Canada
  • theft of medical fentanyl products (mainly skin patches)

Fentanyl is cheap for drug dealers to make into a street drug, compared to other opioids, but it is more powerful. Because only a few grains is enough to kill, fentanyl is causing high rates of overdose and overdose deaths.

Illegal fentanyl and other fentanyl-like drugs, such as carfentanil, are also increasingly being found in other illegal drugs, like heroin. People may be unaware that the drug they are taking is contaminated with fentanyl, which is much more potent.

Drug dealers who make fake pills may not know or control how much fentanyl goes into each pill.

Drugs may also become contaminated with fentanyl accidently when drug dealers re-use surfaces and equipment that have been used for fentanyl.

Fentanyl and its equivalents (analogues) are controlled under Schedule I of the Controlled Drugs and Substances Act. Activities such as sale, possession and production are illegal, unless authorized for medical, scientific or industrial purposes.

What makes fentanyl so dangerous?

Fentanyl is a dangerous drug because:

  • It is 20 to 40 times more potent than heroin and 100 times more potent than morphine. This makes the risk of accidental overdose very high.
  • It is odourless and tasteless. You may not even know you are taking it.
  • It can be mixed with other drugs such as heroin and cocaine. It is also being found in counterfeit pills that are made to look like prescription opioids.

You increase the risk of overdose if you use fentanyl with:

Fentanyl exposure for first responders

Skin exposure to fentanyl is extremely unlikely to harm you immediately.

There are still steps you should take to protect yourself. Find out what you need to know about fentanyl exposure.

Drug-checking services

You can use drug-checking services to find out if drugs contain toxic substances like fentanyl.

To test your drugs go to a supervised consumption site that offers drug-checking services.

Fentanyl test strips have limitations:

  • No fentanyl test strips are specifically designed to check street drugs before consumption.
  • Fentanyl test strips may not detect fentanyl-like drugs, including carfentanil, which may be even more harmful.

Short-term effects of fentanyl

Fentanyl can lead to short-term mental and physical effects.

Mental effects

Fentanyl causes:

  • dizziness
  • confusion
  • going "on the nod" (being in and out of consciousness)

Physical effects

Besides strong pain relief, fentanyl produces effects such as:

  • drowsiness
  • slow breathing
  • nausea and vomiting
  • smaller (constricted) pupils
  • itching or warm/hot sensation on the skin

Life-threatening effects can occur within 2 minutes of use.

Long-term effects of fentanyl

Pharmaceutical opioids have never been studied for long periods of use.

Real-world observations suggest that long-term use of fentanyl may have both mental and physical effects.

Mental effects

Repeated use of fentanyl can cause:

  • substance use disorder
  • depression and suicidal thoughts
  • difficulty in controlling impulsive behaviour

Physical effects

Long-term use of fentanyl can also lead to:

  • constipation
  • substance use disorder
  • sexual problems in men
  • poor nutrition, weight loss
  • irregular menstrual cycles in women

In some patients, particularly at high doses, chronic use of fentanyl can worsen pain.

Fentanyl use during pregnancy can be harmful to your unborn child. It is associated with:

  • miscarriage
  • low birth weight
  • premature delivery
  • high infant mortality

Risks related to fentanyl use

People who do not take fentanyl exactly as prescribed, or who use it for non-medical purposes, usually take it at significantly higher doses than they would receive from a doctor. As a result the harmful effects are much more pronounced.

You are also at a higher risk of overdose with fentanyl than with other opioids. It can be lethal. Life-threatening effects can occur within 2 minutes of use.

You increase the risk of overdose if you use fentanyl with:

If you inject fentanyl, sharing drug equipment can lead to:

Substance use disorder and withdrawal

Tolerance to fentanyl occurs when you need increased doses to produce the same effect. Physical dependence and substance use disorder can develop quickly, within weeks of regular use. Most long-term opioid users experience withdrawal.

During the withdrawal period, you may experience:

  • anxiety
  • nausea
  • insomnia
  • a racing heartbeat
  • abdominal cramping
  • vomiting and diarrhea
  • sweating or cold flashes
  • restlessness and depression
  • intense cravings for the drug

If you are pregnant and using fentanyl, the fentanyl will reach the placenta. This may cause a newborn to have withdrawal symptoms, such as:

  • sweating
  • irritability
  • trouble feeding
  • excessive crying
  • shaky or jerky movements
  • having diarrhea and a need to vomit

A baby with severe fentanyl withdrawal can develop seizures and die.

Babies undergoing withdrawal need to be treated in a hospital.

Signs of a fentanyl or opioid overdose

The signs of a fentanyl overdose are the same as for all opioid overdoses:

  • person is unresponsive
  • slow, shallow breathing
  • gurgling sounds or snoring
  • cold, clammy or bluish skin
  • severe sleepiness or loss of consciousness

If you do use opioids or drugs that may be contaminated with fentanyl:

  • do not use alone
  • carry naloxone and know the signs of an opioid overdose

What to do if you suspect an overdose

If you think someone is overdosing on fentanyl or any other opioid:

  • call 911 immediately for emergency medical assistance
  • use naloxone, a drug that can temporarily reverse the effects of an opioid overdose
    • naloxone wears off in 20 to 90 minutes, so it is important to seek further medical attention
    • give the person another dose of naloxone if signs and symptoms do not disappear or if they reappear
  • stay until emergency services arrive

Staying at the scene of an overdose is important to help save the life of the person experiencing an overdose. The Good Samaritan Drug Overdose Act provides some legal protection for individuals who witness an overdose and call 911 or their local emergency number for help.

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