Interested in starting your healing journey? Speak with an admissions counselor now
We're Hiring!
Apply for Jobs Now

How Long Does Codeine Stay in Your System?

Codeine is a prescription opioid medication used to treat mild to moderate pain. This medication might be prescribed to suppress coughs or to alleviate pain from surgeries or injuries. Codeine is usually combined with other medications like acetaminophen or the anti-nausea drug promethazine. 

While codeine is an effective pain treatment, this substance is also highly addictive. According to the National Institute of Drug Abuse (NIDA), “In 2021, the number of reported deaths involving prescription opioids totaled 16,706.”[1]

For most people, codeine will stay in their system for about 24 hours but can be detected on a urine test for up to two days. Exactly how long codeine stays in the body depends on the dose, frequency of use, and overall health.

How Long Do the Effects of Codeine Last?

How long the effects of codeine last will depend on how much you have taken, your body size, and whether you have consumed other substances. However, if you are taking codeine prescribed by a doctor, it is easier to determine how long the effects will last because the medication is regulated.

Codeine that you receive from a prescription will take about an hour to begin affecting you. You will experience pain relief, drowsiness, and an overall feeling of tiredness. These effects typically last anywhere from 3 to 4 hours after you took the substance.

The common side effects of codeine include:[2]

  • Headaches 
  • Drowsiness 
  • Tiredness and lethargy 
  • Stomach pain 
  • Difficulty urinating 

The severe and less common side effects of codeine include:[2]

  • Agitation
  • Hallucinations
  • Fever, sweating, and confusion 
  • Fast heartbeat 
  • Shivering 
  • Muscle twitches or stiffness 
  • Loss of coordination
  • Nausea and vomiting 
  • Noisy or shallow breathing 
  • Rash, itching, and hives 
  • Changes in vision 
  • Seizures 

If you experience severe side effects, you may be having an abnormal reaction, and you should contact your doctor or emergency medical services immediately.

How is Codeine Metabolized in the Body?

Most medications, including codeine, are processed by the liver upon ingestion. When you take codeine, the substance will travel through your bloodstream and into your liver. Once codeine is in your liver, it will be broken down and eliminated from your body.

The half-life of a drug is how long it takes your body to process half of the substance. Codeine’s half-life is 3 hours. Typically, it takes 4 to 5 half-lives for a substance to be completely removed from your body, which means the entire process can take up to 15 hours.

While most of the codeine will be eliminated from your system within 24 hours, traces of codeine will be left behind in your body for longer. These traces are referred to as metabolites, which are what drug tests look for to determine whether you have abused a drug. 

What Factors Affect How Long Codeine Stays in Your System?

The length of time that codeine remains in your system will depend on a variety of factors. For example, someone who takes large doses of codeine every day will have the substance in their system longer than an individual who only takes the drug occasionally.

Other factors that play a role in how long codeine stays in your system include:

  • The dose you take
  • How long you have taken codeine 
  • How frequently you take codeine 
  • Your age 
  • Weight and body composition
  • Liver and kidney functioning 
  • Whether you take other substances with codeine 
  • Your metabolism and overall health

How Long is Codeine Detectable by Drug Tests?

While the length of time that codeine stays in your system will vary, most people follow the same general timelines. The best way to display how long codeine remains in your body is to discuss how long the substance is detectable by drug tests. Each type of drug test will be able to detect codeine for varying amounts of time depending on how long metabolites remain in that part of your body.


Codeine is eliminated from the body fairly quickly and is only detectable by urine drug tests for 1 to 2 days. 


Codeine can show up in a saliva test as soon as 15 minutes after you take it. However, it will only remain in your saliva for 1 to 2 days. 


Codeine metabolites only remain in your blood for up to 24 hours. As a result, blood tests are not commonly used to detect codeine. 


Hair tests are the most reliable drug tests, as they can detect any substance in your system for up to 90 days. This is because hair grows slowly, allowing the metabolites to remain in that area of your body for a much longer time. 

Find Help for Codeine Abuse and Addiction 

If you or a loved one are addicted to codeine, it’s time to consider professional help. Codeine addiction can take control over every aspect of your life, making it difficult to complete seemingly everyday tasks. By attending a codeine addiction rehab program, you can learn to regain control over your life and maintain long-term sobriety. 

To learn more about our codeine rehab program, contact Mandala Healing Center today. 


  1. The National Institute of Drug Abuse (NIDA): Drug Overdose Death Rates, Retrieved July 2023 From
  2. Medline Plus: Codeine, Retrieved July 2023 From