How Long Heroin Stays in System: Half-Life and Metabolites of Smack

Last Updated: January 26, 2021

Authored by Olivier George, Ph.D.

Reviewed by Michael Espelin APRN

Heroin is an illegal schedule I opioid with an addictive and destructive nature. Many people are unfamiliar with the metabolic activities of this substance, such as how long it takes to break down into secondary substances and how long the opioid stays in the system. This guide provides all the information on how heroin, after ingestion through a specific route, degrades into other detectable substances. The half-life of heroin is 30 minutes; this may vary due to certain factors such as genetics, physical characteristics, amount, and composition of the substance. These variables contribute largely to the complete degradation and production of detectable secondary metabolites in the body.

How Heroin Is Metabolized

People who have experience with heroin use know that it can make them feel differently long after they last used it; this period is much longer than most other drugs. This is because morphine is basically an opiate, which instantly enters the bloodstream. Still, instead of quickly getting detoxified into metabolites, some of it gets accumulated in the fatty tissues. This stored drug continues to re-enter the bloodstream again, slowly over time. This is why the system holds on to heroin metabolites for much longer, even when one stops using it; however, the stored drug may or may not appear on the drug test.

Heroin is a highly potent opioid, and its effect can last longer than some other illicit substances such as meth or cocaine, but the question is, how long does heroin stay in your system? If it takes only about 30 minutes for the half-life of heroin to break down into metabolites, then how is this substance detected days later? Heroin metabolism in the system in reference to body fluids can take 5-6 hours. This is regardless of heroin half-life, with the exception of other parts such as hair follicle and urine; hence this process varies from one individual to the other.

Morphine metabolizes faster if introduced intravenously and slowest if snorted due to the absorption process. These processes determine how long it takes for the opioid to be completely flushed out and become undetectable on heroin test.package of heroin powder.

A person who has a high amount of fatty tissue layers may get a different result on a heroin drug test from someone who has far less. Route of exposure may also play a role; for example, an intravenous intake has the highest bioavailability, which is its highest presence in the system compared to other routes of exposure.

Heroin Detection by Different Types of Tests

Different tests that can detect the presence of morphine have different detection windows and can tell how long heroin stays in your system, with urine tests being the most common as it’s comparatively easy to administer, cost-effective, and less invasive. So how long does heroin last? Let’s take a look at various tests.

The different tests used to detect morphine and their detection times are:

  • Urine test— 2-5 hours after use or 2-3 day for heavy users
  • Saliva test— 1-24 hours after use
  • Blood test— for several hours to 3 days after use
  • Hair follicle test— up to 90 days after use

Hair Follicle Drug Test

Hair drug test has the longest detection window and can detect up to 90 days after the last use. It is so because hair stores the heroin better than the bloodstream. Even when the bloodstream is clean of any drug or opioid metabolites, the hair follicles on the human body can testify to the usage of the drug. There is a flaw with this test as it will not show positive results if the person has used the drug recently, as it takes some time for the drug to appear in the hair.

hair follicle test for heroin.

What Does Heroin Show Up as on a Hair Drug Test?

More sophisticated hair drug tests can reveal more comprehensive results than just positive or negative. For example, with the right heroin testing kits, it can even show the pattern of drug use.

Let’s say the person used the drug for a couple of weeks, abstained for a week, and then used the drug again; the hair test will show pretty accurate data about when the drug was used and when it was not. This provides a rough idea of how to pass a drug test for heroin.

Urine Test

Heroin urine testing depends on the dose of morphine the person takes. In not so heavy users, the heroin urine tests will result positive for up to two to five hours after ingestion, but for heavy users, it could be as long as two to three days after last use. However, heroin in urine is quite rarely detected after a period of three days, except in the case of hardcore users.

Blood Test

The blood test is considered to be the most futile way of detecting morphine, so how long does heroin stay in the blood? As previously mentioned, the morphine usually leaves the system after a few hours. Through a blood test, it is hard to find any heroin because the drug and even its metabolites are swept away from the body rather quickly. This rarely answers the question of ‘how long does it take for heroin to leave the system.’

Moreover, a blood test is usually only carried out if a cop has suspicion over a person and is otherwise generally thought of as invading one’s privacy. A blood test can only result positive for a  user if they have consumed it rather recently. However, the blood test isn’t very common as it’s very invasive, takes very long, and is the most expensive.

Saliva Test

How long can heroin stay in saliva? Being the first line of contact, saliva drug test has the shortest detection time. It can detect the drug after 1-24 hours after use, depending on how much drug the person has consumed. If the person is a heavy user, has a slow metabolism, is not very active, and also uses medication or other substances, the drug could be detected for longer.Mouth swab saliva drug test for heroin.

Saliva tests are not considered invasive, like blood or urine tests. But, unlike a urine test, the saliva test is not very effective when it comes to detecting the levels of heroin present in the body. Not only that, but there is another key factor that contributes to the detection window, and that is the consistency of a person’s saliva. The results may vary substantially from one person to another.

What Determines the Detection Window

The half-life of the opioid is 10-30 min because it is a short action substance. However, many factors can affect how long the drug lasts in the body. Users often ask how long does heroin stay in the system?

Here are Factors that Affect the Period of Heroin Staying in the Body:

  • Amount of substance – Heroin lasts for a varied amount of time in the system. The more drug was consumed, the longer it will last.
  • The quality of the drug – forms of heroin is another key factor that influences the presence of morphine. The low-quality drug usually has harmful chemicals used as additives in it, which can affect the period of the drug in the system and present with heroin side effects in an unpredictable manner.
  • Height and weight – The overall size of the user influences the presence of drugs due to body transport mechanisms. The drug will stay longer in a smaller person’s body compared to a taller, bigger person.
  • Metabolism rate – the period of staying in the system can be affected by metabolic rates, which is faster in men than in women. This breakdown phase also varies in men. The faster the metabolism, the quicker the drug is out of the system. User’s activity level determines their metabolism rate and a more active user’s body will detoxify the body comparatively faster.
  • Tolerance level – long-term users build up a high tolerance for the substance and require more of the drug to attain and maintain the level of high they require. This is dangerous and can lead to heroin overdose symptoms.
  • Age – as a person grows older, metabolic rates drop significantly, making opioids stay longer in the system due to a slower metabolism.
  • Health of Kidney & Liver – the activity of the kidney and liver enables the speedy breakdown of toxins and overall detoxification. If these organs are in poor health due to the misuse of drugs, narcotics, and other substances, then the detection time of the drug would be greatly lengthened.
  • Hydration – bodily hydration improves metabolic activities, which in turn increases the time of detoxification in the body.
  • Body Fat Content – opioids such as morphine are stored in fat, and the more fat a person has in the body, the longer the time of detection of the drug.
  • Genetics – a history of use in the gene can affect tolerance and effectiveness in the body.

How one takes the drug also plays an important role in its detection. Some people may want to know how long does heroin stay in urine if snorted? When taken via intravenous injection, heroin is easier to detect as the bloodstream is filled with it immediately. On the other hand, oral ingestion, snorting, and smoking all have different detection rates. Following IV administration, smoking is the next method that spreads the drug quickly into the bloodstream.

Heroin in the Body – Where it is Stored

How long heroin stays in the system can be answered by understanding the storage mechanism of morphine in the body. It will help one to understand how to get heroin out of their bodies. After it is injected into the bloodstream, heroin is stored in fatty tissues. Over time, the stored drug re-enters the bloodstream in small amounts, causing the person to feel the drug’s effects for some time after having taken it.

Consuming Poppy Seeds Makes Test Positive

A little-known fact is that consuming poppy seeds can actually make one test positive. If one has a drug test coming up, one should stop eating poppy seeds and perhaps conduct a heroin home drug test to ascertain that the test would be negative for opioids. Even though poppy seeds are legal to be consumed, they contain a high level of opioids that could make tests come out positive as heroin is derived from poppy seeds. Eating foods that contain a high amount of poppy seeds can show up on a urine test for up to 48 hours.

Removing Heroin out of the System

There are several things that one can use to assist in detoxifying the body. Here are a few of them:

  • The time of the detoxification window and detox zone, the period of time between which the body is free from all toxins, varies from one individual to the other. Seek professional help in the heroin detox process. Specialists can help to clean up the body in the safest and fastest ways possible.
  • Water and herbal supplements. The use of dietary supplements and herbal cleansers can be effective for systemic detoxification as they react with opioid receptors to metabolize these stored up substances.
  • A highly acidic system can aid in excretion metabolites of narcotics faster. One can take ascorbic acid (vitamin C) to ease withdrawals and quicken the detox process.
  • Green tea iы a known detox agent and can be taken with vitamin B for complete cleansing.

Green tea in a cup on the table.

Treatment for Heroin Addiction

Heroin is a highly addictive substance. It has ruined the lives of many people and led to various forms of crime. Some of the offenders get rehab instead of jail time, depending on the severity of the offense.


Page Sources

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Published on: August 18th, 2016

Updated on: January 26th, 2021

About Author

Olivier George, Ph.D.

Olivier George is a medical writer and head manager of the rehab center in California. He spends a lot of time in collecting and analyzing the traditional approaches for substance abuse treatment and assessing their efficiency.

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.