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How naloxone works

Naloxone (pronounced na-LOX-own) is a fast-acting drug used to temporarily reverse the effects of opioid overdoses.

Naloxone can restore breathing within 2 to 5 minutes. When you take an opioid, it affects certain receptors in your brain. Naloxone works by kicking opioids off the receptors in your brain and binding to those receptors instead. This reverses or blocks the effects of opioids on your body.

Naloxone only works if you have opioids in your system, such as:

  • fentanyl
  • heroin
  • morphine
  • codeine

Naloxone only works temporarily

While naloxone is only active in the body for 20 to 90 minutes, the effects of most opioids last longer. This means that the effects of naloxone are likely to wear off before the opioids are gone from the body, which causes breathing to stop again.

Naloxone may need to be used again, depending on the amount or type of opioid taken, or how the opioids were taken (for example: oral, injection).

If you suspect an overdose:

Naloxone is safe

Naloxone is safe for all ages. It only works if you have opioids in your system. You cannot use naloxone improperly and does not create dependence. It is safe to keep a naloxone kit on hand.

Types of naloxone kits available

In Canada, two types of take-home kits are available:

Where to get naloxone in your province or territory

Take-home naloxone kits are available at most pharmacies. A prescription is not needed. Ask the pharmacist.

Some provinces offer free take-home naloxone kits. Consult your province to see where these kits are available.

How naloxone is helping to address Canada's opioid crisis

Naloxone kits have successfully reversed thousands of overdoses across Canada.

Naloxone is used by first-responders, including paramedics and firefighters. Take-home kits are also available at most pharmacies or local health authorities for anyone who is at risk of an overdose or who is likely to encounter one.

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