Get Help & Answers Now

How can we help?

I'm ready to sign up! I have a few questions I want to refer someone Quiz: is Suboxone for me?

How Long Does Morphine Stay in Your System?

Elena Hill, MD, MPH profile image
Medically Reviewed By Elena Hill, MD, MPH • Updated Aug 14, 2023 • 7 cited sources

Morphine stays in your bloodstream for about four hours, but it can show up in drug tests for much longer.

Most morphine prescriptions come with a four-hour dosing schedule, suggesting the drug remains active for about that long. 

Duration of Morphine’s Effects

How long you feel morphine’s effects depends on the product you’re using and how you ingest the drug. These general guidelines can help you understand the differences: 

Oral Morphine

Doctors use morphine tablets and capsules to address moderate to severe pain. It may be prescribed for pain related to cancer or for pain related to a major surgery or injury. Two basic forms of morphine tablets or capsules exist:

Immediate-release tablets typically last between 2 and 4 hours.[1]

Extended-release formulations (like MS Contin) last between 4 and 12 hours when taken orally.[2] 

Snorted Morphine

If morphine is misused via snorting, it enters the body through the mucosal membranes of the nose and then into the bloodstream. The individual will likely feel changes immediately (within a few minutes), and the effects usually last a few hours. 

Injected Morphine

Morphine injections are designed for severe pain that doesn’t respond to oral formulations. Doses are typically administered every four to eight hours. [3]

Morphine Suppositories 

Some people with advanced medical conditions can’t swallow morphine or receive it by injection. For these individuals there are morphine suppositories, also usually given every four to eight hours. [4]

How Long Does Morphine Remain in Your System?

Morphine stays in the blood for no more than a few hours, meaning the active effects of morphine only last a few hours. However the metabolites of morphine stay in the body and are detectable in the urine for several days. [5] Morphine can be detected in various body components as follows:

  • Sweat tests: Up to 14 days
  • Saliva tests: Up to 36 hours
  • Urine tests: Up to 3 days
  • Hair tests: Up to 90 days

Factors that could make morphine show up for longer or shorter periods include the following:[6]

  • How long you’ve been taking morphine
  • How much morphine you use every day
  • How quickly you metabolize the drug 

How Does Your Body Break Down & Metabolize Morphine?

Morphine is metabolized mostly in the liver. [2] Some people have genetic alterations allowing them to break down morphine faster than others. But some people have opposing alterations, so morphine persists much longer. Most people metabolize morphine within four hours but some may metabolize more rapidly or more slowly. 

Understanding Morphine’s Half Life

The half-life of a drug represents the period required for the body to metabolize half of the drug.[7] Morphine, has a half-life of two to four hours.[2] Half-life can be extremely variable, and some people may experience effects of morphine for shorter or longer periods than others.

Medically Reviewed By Elena Hill, MD, MPH

Elena Hill, MD; MPH received her MD and Masters of Public Health degrees at Tufts Medical School and completed her family medicine residency at Boston Medical Center. She is currently an attending physician at Bronxcare Health Systems in the Bronx, NY where ... Read More

  1. Morphine Sulfate Oral Immediate-Release Pill. OncoLink. September 2021. Accessed April 2023.
  2. MS Contin. U.S. Food and Drug Administration. 2009. Accessed April 2023.
  3. Morphine Injection. U.S. National Library of Medicine. February 2021. Accessed April 2023.
  4. Morphine Rectal. U.S. National Library of Medicine. February 2021. Accessed April 2023.
  5. Opioid Testing. Testing. September 2022. Accessed April 2023.
  6. More FAQs About Opioids. National Institute on Drug Abuse. July 2018. Accessed April 2023.
  7. Relevance of Half-Life in Drug Design. Journal of Medicinal Chemistry. November 2017. Accessed April 2023.

Download Our Free Program Guide

Learn about our program, its effectiveness and what to expect

Safe, effective Suboxone treatment from home. Learn More

Imagine what’s possible on the other side of opioid use disorder.

Our science-backed approach boasts 95% of patients reporting no withdrawal symptoms at 7 days. We can help you achieve easier days and a happier future.