How Long Do Opioids Stay in Your System?

Broadly, opioids exist in two groups: long-acting opioids and short-acting opioids. Typically, urine testing is used to detect opioid use, with a detection window of one to three days for most short-acting opioids and one to 14 days for long-acting opioids. 

However, this isn’t universally true. The drug heroin is short-acting and has a detection window of less than one day if testing urine. Regardless, hair testing has a much longer detection window in ideal conditions but also a variety of limitations not present with urine testing.

List of Opioids & Their Detection Timelines

The following table lists some of the most common opioids and the estimated window of detection regarding those opioids for different types of drug testing:[1,2]

Looking at the table above, you may notice three drugs that stand out as unusual compared to the windows of other opioids. Buprenorphine and methadone are two long-acting opioids, often used in addiction treatment. These drugs spend much longer in the body than short-acting opioids and, as such, have significantly longer detection windows. 

Meanwhile, heroin is especially short-acting. Because of this, it has a much shorter detection window than many other opioids.

Urine testing is much more common than blood testing, as it often has a comparable or better detection window, requires less expertise to conduct, and is less invasive. The only real advantage of blood testing is that it is harder to actively cheat a blood test. 

Note on Hair Testing

Hair testing has an especially long detection window, but this type of testing has limitations. As it’s often considered fairly invasive and expensive, this type of testing is relatively rare. It also requires time for a person’s hair to grow enough for it to show signs of past drug use.[2] 

Furthermore, the exact detection window can vary significantly, especially depending on how a person cuts their hair. This type of testing usually involves collecting a sample of about 50 to 100 strands of hair for testing.[2]

One can imagine hair as something of a timeline of a person’s drug use. The more a person engages in drug use and the longer the hair is, the more likely that drug use can be detected in this way. 

Opioids Half-Life & Its Impact on Your System

All drugs have an elimination half-life. After one half-life has passed, 50% of the initial drug amount is removed from the body. After about four to five half-lives have passed, 94% to 97% of a drug will have been eliminated from the body.[3]

Different opioids have different half-lives, which means they will remain in the body for different lengths of time. Opioids that last especially long in the body tend to be less potent, but the reverse isn’t entirely true. Some opioids like fentanyl last longer than others like morphine or heroin but have a higher potency (in the case of fentanyl, much higher). 

A drug’s effect weakens over time. The length of time an opioid is likely to affect you can vary, but it won’t need to be fully eliminated before its effects become negligible. What this means is that an opioid can be detectable in the body for longer than it affects a user. 

Factors That Can Impact Detection Time With Opioids

The exact detection window for an individual’s drug use can vary significantly. Two major factors include the frequency of drug use and the severity of that use. The more frequently a person abuses opioids and the greater amount of opioids they abuse, the more likely the detection window is to be extended.

Metabolism also affects an individual’s detection window, with a slower metabolism meaning a drug spends a longer time in the body. Metabolism tends to slow as we age and can be affected more severely by some medications and health conditions, especially health conditions affecting the liver. Metabolism can also be affected by genetics, with some people just predisposed to have an unusually fast or slow metabolism.[4]

Notably, a slower metabolism will also extend the effects of opioids. Some people with especially slow metabolisms may even experience an overdose at unusually low doses.[5] A doctor can factor this into a prescription, but someone will need to keep this in mind if they misuse or intentionally abuse opioids.