How Long Does Heroin Stay in Your System?

White powder in a spoon with a syringe and pills.

Heroin is an illegal opioid. Heroin comes from morphine and when someone uses it they experience a euphoric high. Drowsiness and even sedation follow that high. Heroin is a central nervous system depressant. The drug crosses the blood-brain barrier quickly and binds to opioid receptors. Using heroin can cause addiction to develop quickly. Unfortunately, the drug is popular due to its fast-acting potency. Approximately 170,000 people tried heroin for the first time in 2016 — almost twice the amount from a decade prior.

So heroin is a popular and potent drug, but how long does heroin stay in your system? While the most intense effects of being high on heroin last anywhere from 45 seconds to a few minutes, heroin stays in the system longer. Generally, heroin stays in the system for a few hours, but it can be detectable in a drug test for longer than that.

How Does Heroin Work?

People often ask, “How does heroin work?” When someone uses heroin, it affects their brain and central nervous system. Specifically, heroin works by binding to opioid receptors. When opioid receptors are activated, it changes how signals move between the brain and body, which is why opioids have pain-relieving properties.

The use of heroin also causes a euphoric high and it slows all the functions controlled by the central nervous system. When someone uses heroin, the slow down of the central nervous system is what causes them to feel drowsy and often fall asleep when the high dissipates. Breathing, heart rate and blood pressure all slow due to the effects of heroin.

Heroin creates euphoria by triggering a release of large amounts of “feel-good” neurotransmitter, dopamine. That causes a reward response in the brain because the brain is wired to want to seek out stimuli that create pleasure. This reward response activation is why heroin is so addictive.

What Is the Half-Life of Heroin?

You may have heard people mention opioid half-lives, but never considered asking, “What is the half-life of heroin?” The half-life of a substance indicates how long it takes the concentration of that substance to be reduced by half in the body. The half-life of heroin is very short: around two to six minutes. It may take four to five half-lives for the complete elimination of a substance to occur, but the elimination rate varies based on many factors.

Some of the factors that affect the half-life of heroin and how long it stays in your system include:

  • Liver and kidney health
  • Metabolism
  • How much heroin was used
  • Body fat percentage
  • Age
  • General health
  • Genetics
  • Hydration level

As far as drug tests, heroin can be detectable in urine tests for an average of two days. Some tests might be able to detect the use of heroin for up to seven days after someone last used it. In blood and saliva tests, heroin is usually only detectable for anywhere from five to six hours, but it’s possible for a test to show heroin use for up to two days after the previous use. A hair follicle test can indicate heroin use for up to three months after someone last used the drug.

Metabolism of Heroin

The metabolism of heroin occurs primarily in the kidneys. Heroin is eliminated through urine, although some heroin leaves the body through saliva, tears, sweat and feces. When someone uses heroin, it metabolizes quickly, which is why the half-life is so short.

Even though heroin metabolizes quickly, it leaves behind metabolites which can stay in the system longer. Heroin metabolizes into 6-monoacetylmorphine (6-MAM) and then morphine. Some drug tests may screen for these metabolites.

Get Help for Heroin Addiction

Heroin is an incredibly addictive and dangerous drug, but help is available. If you’re struggling with heroin, or you have a loved one who is, please contact The Recovery Village at Palmer Lake to learn more about the treatment programs available. Individualized treatment programs cater to patient’s specific needs by addressing the addiction along with any co-occurring disorders. Call today and take the first step toward a healthier future.


Buddy T. “How Long Does Heroin Stay In Your System?” Verywell Mind, November 8, 2018. Accessed March 1, 2019.

NIH National Institute on Drug Abuse. “Heroin.” June 2018. Accessed March 1, 2019.