How Long Does Demerol Stay in Your System?

Demerol (generic name, meperidine) is an opioid that has been used to treat stiffness, shivering after surgery, and short-term pain when other opioids haven’t been effective. As the body metabolizes the Demerol/meperidine, it could become toxic, and people should use caution when using it or other opioid medications.

Commonly known as Demerol, meperidine hydrochloride is a powerful opioid drug that has been prescribed to alleviate severe pain when other opioids haven’t been effective. It has also been used to treat drug-related stiffness and shivering after surgery. Because it’s so powerful, people shouldn’t take Demerol/meperidine for extended periods of time.

Because of its potency, people might wonder, How long does Demerol stay in your system? and  Does Demerol show up in a drug test? Understanding the drug and its effects can answer these questions and others.

How long does Demerol last?

Answering how long Demerol could last might be tricky, and it might help to understand what a half-life is. A half-life of a drug is the amount of time it takes for the plasma concentration (the maximum concentration of a drug in the body) to reduce by one half.

Meperidine, the generic form of Demerol, has a half-life of around two to five hours, which means half the amount of drug is gone from adults’ bodies in that time. But while a Demerol half-life is two to five hours, the body also metabolizes meperidine to another substance, normeperidine.

Normeperidine has a much longer half-life of 15 to 30 hours. For people with kidney problems, the half-life can be even longer, 35 or 40 hours. While it’s less potent as a pain reliever than meperidine, normeperidine can be a neurotoxin, which means it can kill nerve cells.

People with kidney problems or people who take additional doses of meperidine might experience various symptoms when it’s converted to normeperidine, including:

  • Hallucinations
  • Tremors
  • Seizures
  • Muscle twitching or jerking
  • Anxiety

Although meperidine or normeperidine are similar, their differences can be striking.

How long is demerol detectable in urine?

While the body works to metabolize Demerol/meperidine, the substance and related products can linger. Demerol drug tests are needed to determine the presence of the substance because meperidine is a synthetic drug that other types of screenings might miss.

How long does Demerol stay in your urine? The answer is typically one or two days for meperidine. However, the Demerol drug test detection time for normeperidine is one to four days because that substance has a longer half-life and lingers longer in the system.

Demerol/meperidine can relieve stiffness, shivering, and pain. It can also cause serious complications, especially in people who are using other drugs. As with other opioids, people should use it with caution and under medical supervision.

Sources – Demerol® (meperidine hydrochloride, USP) – Is Meperidine the Drug That Just Won’t Die? – Drug Plasma Half-Life and Urine Detection Window

Medical disclaimer:

Sunshine Behavioral Health strives to help people who are facing substance abuse, addiction, mental health disorders, or a combination of these conditions. It does this by providing compassionate care and evidence-based content that addresses health, treatment, and recovery.

Licensed medical professionals review material we publish on our site. The material is not a substitute for qualified medical diagnoses, treatment, or advice. It should not be used to replace the suggestions of your personal physician or other health care professionals.

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