Opioid Half-Life – Know How Long They Will Last in your System

Opioid prescriptions and addiction are part of daily life for many people in the United States. According to the U.S. Centers for Disease Control and Prevention, there were more than 191 million opioid prescriptions dispensed in the U.S. in 2019. Between 8 and 12 percent of people who abuse prescription opioids develop a substance use disorder. Understanding more about opioids and how they affect you can help prevent problems with opioid use.

Whether you have been using an opioid medication, or you’ve been using an illicit opioid, it’s important to know how long the drug will remain in your system. If you plan to take an opioid, how long will you feel its effects? If you are continuing to take an opioid, when is it safe to take your next dose? If you’ve recently stopped using an opioid, how long will it show up on drug screens?

When considering how long an opioid stays in your system, you might be thinking about two questions: “How long will an opioid remain effective and active in my body?” and “How long will an opioid be detectable in my body?”

Though they sound similar, these are  different questions with different timelines. There are many different types of opioids, and each one can have different schedules as they are processed in your body. However, there are a few opioids that you are most likely to encounter through prescription or illicit use.

Half-Life and Duration of Action

A drug’s half-life is how long it takes to be reduced to half of its original concentration in your blood. In most cases, the duration of a drug of action (or the amount of time you feel its effects) is very similar to the drug’s half-life. The major exception to this rule are drugs that break down into psychoactive metabolites.

In other words, certain opioids can be broken down into different opioids that last longer and continue to affect your brain and body. However, understanding half-life and duration of action can tell how long you have before a drug will start to lose strength. Below are key time periods for each of the most common opioids:

  • Hydrocodone has a half-life of up to four hours, and it is almost eliminated from your blood in six hours. You can feel its pain-relieving effects for up to eight hours before it starts to wear off.
  • Morphine will start to be effective after 30 to 60 minutes when taken by mouth, and faster when injected. Its half-life is two to four hours. The effects will last four to six hours unless you take the extended-release version, which can be double that.
  • Oxycodone has a half-life of 3.2 hours, and extended-release versions can have half-lives that last five hours. It may be eliminated from the blood after 22 hours. You will feel the effects of oxycodone between three and four hours.
  • Hydromorphone has a half-life of two to three hours. It can start to take effect after 15 to 30 minutes and peaks after 60 minutes. It lasts for another two to three hours after that.
  • Heroin has among the fastest half-lives at around two to six minutes. However, its effects can last for up to five hours because the body converts it to morphine, which has a much longer half-life. When injected, its effects can be felt immediately.
  • Fentanyl has a half-life of 90 minutes. You may feel its effects between 30 and 60 minutes. The drug starts to work in less than a minute and reaches its peak effects at five minutes.

Drug Testing

There are various reasons you might need to get a drug test. Most people must submit a drug test


because an employer or a potential employer requires it. Athletic organizations may also require one. People in addiction recovery might have to take multiple drug tests during treatment or when they live in sober living environments. Taking a drug test as part of a criminal investigation is also common.

The length of time an opioid can be detected in your blood depends on the type of drug test you take. For the most part, drug screens that test for recent drug use will use a urine sample. It’s the most reliable, and this kind of will detect drug use that has occurred within the past week.

Saliva tests are less reliable, but they are easier to do and less invasive. Blood tests have the shortest window of accuracy and only be effective only within a few hours. These may be used in criminal investigations to establish very recent drug use.

Hair tests are the longest, as they can detect drug use months later. These tests are controversial because it’s argued that they don’t establish recent drug use. Someone could go through a full round of addiction treatment and still test positive after taking a hair test.

When it Comes to Urine Testing, Opioids Can Be Detected in the Following Periods:

  • Hydrocodone can be detected in your urine for up to three days.
  • Morphine can be found in a urine test for up to three days.
  • Oxycodone can be detected in the urine for up to four days.
  • Hydromorphone can be detected in urine for two to three days.
  • Heroin can be detected in the urine for up to a week.
  • Fentanyl can be detected in the urine for between one and two days.

Seeking Addiction Treatment

If you or someone you know is struggling with a substance use disorder that involves opioids, it’s important to seek addiction treatment as soon as possible. Opioid use disorders are notoriously difficult to get over on your own. Addiction, in general, is a progressive disease that usually worsens over time. If not addressed, opioid use disorder can threaten your health, finances, relationships, and legal standing.

However, addiction is a treatable disease. Getting early treatment can help you to avoid some of the worst consequences of addiction, such as long-term health complications. But no matter where you are in the disease, effective help is available. Learn more about opioid addiction and how it can be treated to start your road to recovery today.

Tap to GET HELP NOW: (844) 318-7500