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How Long Does Codeine Stay In Your System

Key Points

  • Codeine is a prescription opiate analgesic used to help patients with pain management.
  • There is no fixed duration for codeine to leave a person’s system completely; the time it takes to metabolize fully will depend on different variables.
  • Some primary factors impacting the length of time codeine remains in the system are body fat percentage, age, organ function, other medications, and certain genetic factors.
  • The common types of drug testing available for identifying the presence of codeine in the body are urine, blood, and saliva tests.

Codeine is a commonly prescribed medication typically given to individuals who experience moderate to severe pain as well as to help reduce excessive coughing. However, much like with all prescribed medications, codeine does have specific properties that can remain detectable over time depending on the dosage taken and other patient variables.

What is Codeine?

Codeine is a medically prescribed drug that is classified as an opiate analgesic.[1] This medication is primarily given to help manage pain, including temporary relief to persistent coughs caused by common colds or the flu.

The medication decreases brain activity while binding to certain receptors responsible for the sensation of pain. By limiting nervous activity in these areas, patients can experience temporary pain relief while the body works to address the source of pain.

Codeine can be prescribed as a single-ingredient medication but is most commonly prescribed as a combination drug with acetaminophen or aspirin.

How Long Does Codeine Stay in Your System?

There is no fixed duration associated with the presence of codeine in an individual’s body, and the speed at which an individual metabolizes the drug completely will depend on several different factors.

When considering the total time it takes for codeine to leave the system, it’s first important to understand how long the drug provides effective relief. On average, testing associated with the half-life of codeine shows an average of 2 to 4 hours across various test subjects and formats.[2]

The focus of these tests helps better understand the halfway point of when initial doses start to be eliminated from most people’s systems. However, the actual answer to how long codeine takes to be “completely” removed isn’t straightforward since the drug can also be converted into a different metabolite in the body – morphine – which can last much longer in the system.[3]

What are the Factors That Impact How Long Codeine Stays in the Body?

Several unique, individual factors come into play when considering how long codeine will stay in someone’s system. Below are some of the most common variables that will impact the length of time the drug is eliminated from the body:

  • Body Fat Percentage: Many opiate drugs like codeine are considered Lipophilic (fat-soluble) in nature.[4] This means they tend to have a larger volume of distribution in individuals with higher body fat, which can impact the concentration of the drug in the bloodstream, impacting its therapeutic effect and length of stay in the system.
  • Age and Organ Function: A person’s age and the condition of their critical body organs can also impact a body’s ability to rid itself of toxic drugs. The liver is the primary site for codeine metabolism.[5] Any impairment in liver function, such as from liver disease, can affect the rate at which codeine is metabolized.
  • Use of Other Medications: Taking codeine with prescribed or unprescribed medications can influence codeine metabolism. Certain drugs can either inhibit or reduce CYP2D6, which can change how effectively the drug is converted into morphine and then fully metabolized.[6] Medications known to have this effect when used in combination with codeine include duloxetine, paroxetine, fluoxetine, bupropion, and amiodarone drugs.
  • Genetic Influencers: Codeine is metabolized into its active form, morphine, primarily by the enzyme CYP2D6. Variability in the CYP2D6 gene can significantly impact the rate of metabolism.[7] Based on their CYP2D6 activity, individuals can be classified as poor, intermediate, normal, or ultrarapid metabolizers. Poor metabolizers may experience reduced codeine efficacy, while ultrarapid metabolizers may have an increased risk of toxicity due to higher morphine levels.

What Kind of Drug Tests Are Used to Detect Codeine?

Drug tests to detect codeineVarious drug tests can detect codeine and its metabolites in the system. While certain tests may be more widely used than others when looking for the presence of opioids, each test type has effective testing windows where accurate measurements can be taken.[8]

  • Urine Tests: The most common method for detecting codeine in a system is through urine testing. This is one of the fastest and most non-invasive methods for detecting opiates in someone’s system and is effective for accurate detection within 1-4 days after use, depending on dosage and individual metabolism.
  • Blood Tests: Blood testing is another common method for measuring the actual amount of codeine present in the bloodstream. This is often used in life-threatening situations when a potential overdose has occurred and can be used to detect levels of opiates in the blood within a few hours to 1-2 days hours after use.
  • Saliva Tests: Saliva testing is another test used to screen for certain drugs, although less commonly used than other testing methods. Saliva testing has a shorter window than most tests and is usually only effective up to 48 hours later. While these tests can be used, they often are not as accurate when detecting lower levels of codeine or its metabolites.

Does Codeine Contain Addictive Properties?

As an opiate analgesic, codeine does have addictive properties that can be intentionally or accidentally abused when not following strict prescription instructions. Codeine has a lower risk of addiction compared to more potent opioids like morphine or oxycodone.

The risk of addiction can increase over time depending on how long the drug is used or the amount of dosage consumed. Individuals with a predisposition to substance abuse are highly advised to express these concerns to their doctor to decide if the use of codeine is the best option for pain management.

What are the Signs of Codeine Addiction?

Developing a chemical dependence on codeine can happen with frequent use of the drug and isn’t always noticeable in its early stages.[9] However, individuals need to recognize the signs that they have become addicted to the substance so they can seek the treatment support they need.

Common signs of codeine abuse or withdrawals include:[10]

  • Increased agitation
  • Being highly anxious
  • Muscle and body aches
  • Lack of sleep (insomnia)
  • Excessive sweating
  • Abdominal cramping
  • Nausea
  • Vomiting

Symptoms of withdrawal typically begin to show within 12-24 hours after the last use of codeine. They can grow in intensity after that period when additional doses of the drug haven’t been taken.

Get The Support You Need to Overcome Codeine Addiction

Addressing codeine addiction on your own can be challenging, considering the uncomfortable nature of withdrawal symptoms and the potential danger they can cause. Help is always close by if you need additional support to overcome addiction and live a healthier life.

Frequently Asked Questions

Common side effects of codeine include drowsiness, dizziness, constipation, nausea, and vomiting. Serious side effects include shallow breathing, severe drowsiness, confusion, and allergic reactions. Long-term use can lead to dependence and withdrawal symptoms, so it’s important to follow prescription instructions provided by your doctor strictly.

Yes, it is possible to get addicted if you do not take the drug as prescribed. Codeine is an opioid, and like other opioids, it has the potential for abuse, leading to physical and psychological dependence. Misuse of codeine can result in overdose and death, particularly when taken in higher doses or combined with other substances.

Codeine can interact with certain medications, which may increase the risk of serious side effects. It’s important to inform your healthcare provider of all your medications, including over-the-counter drugs and supplements. While a doctor may prescribe a safe combination of codeine and other drugs, combining codeine with alcohol, sedatives, or other central nervous system depressants can be life-threatening.

To take codeine safely, follow your healthcare provider’s instructions precisely. Do not take more than the prescribed dose, and do not take it more frequently than recommended. Avoid alcohol and other depressants while using codeine. Contact your healthcare provider immediately if you have any concerns or experience severe side effects. Never share your medication with others, especially with someone who has a history of drug abuse or addiction.

If you miss a dose of codeine, take it as soon as you remember. However, if it is almost time for your next scheduled dose, skip the missed dose. Do not take an extra dose to make up for the missed one, as this can increase the risk of side effects and overdose.

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[1] U.S. National Library of Medicine. (n.d.). Codeine: Medlineplus drug information. MedlinePlus. retrieved on May 23, 2024.

[2] G;, F. G. B. T. (n.d.). [pilot study of the metabolism of codeine to morphine and a possible modification by benzodiazepines]. Beitrage zur gerichtlichen Medizin. retrieved on May 23, 2024.

[3] Dean, L. (2021, March 30). Codeine therapy and CYP2D6 genotype. Medical Genetics Summaries [Internet]. retrieved on May 23, 2024.

[4] [5] Smith, H. S. (2009, July). Opioid metabolism. Mayo Clinic proceedings. retrieved on May 23, 2024.

[6] [7] Dean, L. (2021a, March 30). Codeine therapy and CYP2D6 genotype. Medical Genetics Summaries [Internet]. retrieved on May 23, 2024.

[8]McNeil, S. E., Chen, R. J., & Cogburn, M. (2023). Drug testing. In StatPearls [Internet]. Retrieved from retrieved on May 23, 2024.

[9][10] U.S. National Library of Medicine. (n.d.-b). Opiate and opioid withdrawal: Medlineplus medical encyclopedia. MedlinePlus. retrieved on May 23, 2024.

Last medically reviewed June 10, 2024.