Heroin is an illicit opioid people often snort, smoke, or inject in order to get high. Heroin is extremely short-acting with a half-life of only about 6-15 minutes, which means it only stays in your system for just a few hours.
However, heroin can be detected on drug tests for longer than it stays in your system. Here are the heroin detection windows, broken down by test type:
- Urine: 1 day
- Blood: Up to 6 hours
- Saliva: Up to 6 hours
- Hair: 90 days or more
If you are searching for how long heroin stays in your system, you may be struggling with heroin use or addiction. Professional treatment is available and can help you on the road to recovery.
How Heroin’s Half-Life Affects How Long It Stays in Your Body
A drug’s half-life refers to the length of time it takes for the body to reduce the drug’s levels by 50%. Heroin’s half-life of between 6 and 15 minutes is extremely short compared to most other drugs. 
Because the half-life is so short, that means the amount of heroin in the body is cut by 50% every 6-15 minutes. As such, within one hour, the heroin in a person’s body is already down to about 6% of what it was at the time of use. And within two hours, it’s nearly entirely eliminated.
How Long Can Heroin Be Detected on A Drug Test?
Because heroin only stays in your system for a couple of hours, the detection window for this opioid is also very small.
Heroin can only be detected in urine for about one day, blood and saliva for about 6 hours, sweat for two weeks, and hair for about three months. 
Heroin Detection Window
|Type of Test||Detection Window|
|Blood||Up to 6 hours|
|Saliva||Up to 6 hours|
|Sweat||Up to 14 days|
|Blood||About 90 days|
Factors That Affect How Long Heroin Stays in Your System
Although heroin generally stays in your system for just a few hours, the exact amount of time depends on many factors, such as:
- Liver and kidney functioning
- Heroin purity
- Amount of heroin used
- Frequency of use
- Height and weight
- Body fat content
Additionally, individual factors affect how long heroin is detectable in various drug tests. These influences include:
- Type of drug test administered
- Patient health
- The use of other medications
- Patient nutrition
- Average dose of heroin used
Typically, drug tests will be able to detect heroin for longer if you use it heavily than if you occasionally use it.
How Does Heroin Affect the Body?
Heroin is associated with a rapid, intense euphoric high. It is a short-acting drug considered to have significant abuse and addiction potential because of its rapid onset of effects, rush of pleasure, and short-lived high.
- A “twilight state” where one falls in and out of consciousness
- Respiratory depression
- Constricted pupils
- Warm flushing of the skin
- Dry mouth
- A feeling of heaviness in the extremities
Heroin can cause physical dependence and addiction. With repeated use, the body can adapt to the drug, causing a person to experience distressing withdrawal symptoms that typically feel like the flu. Heroin withdrawal can be managed in a medical detox setting, followed by comprehensive addiction treatment.
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- Drug Plasma Half-Life and Urine Detection Window. (September 2022). ARUP LABORATORIES.
- Heroin. (November 2022). Drug Enforcement Administration.
- Opioid Testing. Testing.
- Clinical Drug Testing. (August 2022). StatPearls.
- Interpretation of Opiate Urine Drug Screens. HealthPartners.