How Long Does Morphine Stay in Your System?

The length of time morphine stays in your system depends on several factors. In most people, morphine stays in the body for up to three days, and urine tests can detect morphine use for three days.
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Morphine is a quick-acting drug. Its effects last between four and six hours, and the prescription drug is removed from the blood in about 15 hours. Drug tests can detect morphine for longer periods of time.

Lengths of time morphine can be detected by common tests:

  • Urine test: One to three days.
  • Saliva test: Between 24 and 36 hours.
  • Hair test: Up to 90 days.

It takes up to three days for the body to remove morphine. After three days, traces of the drug are undetectable in saliva and urine. Hair tests may be able to detect the drug for up to 90 days, but hair hair tests aren’t commonly used by employers or rehab facilities.

Rehabs use drug tests to motivate clients to stay sober. Inpatient facilities also use the tests to make sure clients aren’t sneaking drugs into the facility.

If you know you have to pass a drug test and you’re unable to quit using the drug, you may have a morphine addiction. Addiction is a complex disease that makes it difficult for a person to quit using drugs.

Morphine Metabolism

Metabolism refers to what happens to a drug inside the body. Morphine can be swallowed, snorted, injected or administered rectally. It isn’t absorbed through the skin.

The method of administration determines how quickly morphine enters the blood stream. When it’s injected, peak levels of morphine accumulate in the blood within 20 minutes. It takes between 30 and 90 minutes for morphine levels to peak in the blood when the drug is swallowed.

You feel the effects of morphine more quickly when it’s injected because the drug goes straight to the brain. When it’s swallowed, morphine travels to the liver before it reaches the brain. The liver breaks some of the morphine down into other chemicals called metabolites.

Morphine metabolites include:

Some metabolites exit the body with urine. The remaining morphine stays in the blood and travels to the brain. In the brain, morphine causes pain relief, relaxation and various side effects.

The drug then travels through the body until it reaches the liver again. This cycle continues until morphine is completely removed from the body.

Heroin and codeine are converted to morphine in the body. Thus, a positive drug test for morphine indicates the use of morphine, codeine or heroin.

Half-Life of Morphine

A substance’s half-life is the amount of time it takes for half of the substance to be eliminated from the blood. For example, if someone injects 10 milligrams of morphine, a half-life is the amount of time it takes for the body to eliminate five milligrams.

The half-life of morphine is between two and 3.5 hours. The half-life varies because some people metabolize morphine more quickly than others.

Factors affecting how long morphine stays in the blood include:

An insignificant amount of morphine — about 3 percent of the original dose — remains in the blood after five half-lives. Depending on various factors, morphine stays in the blood for between 10 and 15 hours. It can still be detected by tests because it takes one to three days for the body to excrete the drug in urine.

Morphine is a powerful drug. In high doses, it can cause death. Other morphine side effects include vomiting, diarrhea, slowed breathing and fainting. If you’re unable to stop taking morphine long enough to pass a drug test, you may have a prescription drug addiction that requires rehab. Treatment for addiction can save your life.

Medical Disclaimer: aims to improve the quality of life for people struggling with a substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare provider.

Chris Elkins, MA
Senior Content Writer,
Chris Elkins worked as a journalist for three years and was published by multiple newspapers and online publications. Since 2015, he’s written about health-related topics, interviewed addiction experts and authored stories of recovery. Chris has a master’s degree in strategic communication and a graduate certificate in health communication.
Kim Borwick, MA

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