When people go online and search for information about drugs – whether they’re looking for information on a prescription medication, an over-the-counter-medication, or something else – one common question they type in the search bar is “How long do/does [insert names of drugs] stay in my body?”
It’s an important question for a variety of reasons.
From a patient perspective, knowing how long drugs stay in their body helps them understand more about the drug they’re taking and why they’re on the dosage schedule they’re on. It also helps them avoid any dangerous interactions with other medications and prevents unwanted side-effects related to missed or incorrect dosages.
Knowing how long drugs stay in the body helps clinicians for the same basic reasons. They need to know how a potential medication might interact with other medications a patient takes and affect other medical conditions the patient might have. For clinicians with patients in treatment for alcohol or substance use disorder (SUD), the information is essential for understanding when withdrawal starts and ends, which has a direct impact on when a patient can participate in various treatment activities.
In addition, for clinicians with patients with opioid use disorder (OUD) or SUD, the length of time an opioid – or alcohol – stays in their system determines when that person can initiate medication-assisted treatment (MAT) with certain medications for opioid use disorder or medications for alcohol use disorder.
What Happens to a Drug Inside Your Body?
When you ingest a drug, your body breaks it down into its constituent parts. Some of those parts serve a purpose, like relieving pain, reducing swelling, or decreasing anxiety, for example. The remaining parts of the drug are treated by the body as waste. These extra waste products are processed through the kidneys, lymphatic system, or liver, and subsequently eliminated through various means. The time it takes for the body to completely eliminate a substance depends on a variety of factors, including:
- The drug itself
- Dosage of the drug
- Presence of other drugs
- Age
- Weight
- Gender
- Liver/kidney function
When discussing how long a drug stays in the body, one term clinicians and scientists use frequently is half-life. The half-life of a drug is the length of time it takes for the concentration of a drug in the body to drop by fifty percent of its original dosage/concentration. Half-life does not refer to how long a drug stays in your body overall: that’s determined by the factors we list above.
While the half-life of a drug doesn’t define its onset of action – i.e., how long it takes to start working – it does help prescribers determine how frequently a medication should be taken to maintain a consistent therapeutic effect.
Medication and Addiction
In addiction treatment, understanding the half-life of a drug is essential in determining several important things:
- When withdrawal – the reaction of the body to the absence of a drug – will begin and end
- Whether specific physical, psychological, and emotional symptoms are a result of withdrawal, a co-occurring disorder, or something else
- Patients with opioid use disorder (OUD) who want to engage in medication-assisted treatment (MAT) with Vivitrol® must completely detoxify from opioids before taking their first dose of medication
- Patients with alcohol use disorder (AUD) who wants to engage in medication-assisted treatment (MAT) with Vivitrol® must completely detoxify from alcohol before taking their first dose of medication
Here are the lengths of time the most common substances of misuse stay in your body. We know this information based on how long these drugs are detectable by typical drug tests or screens. Below, we’ll share three things:
- How long a drug is detectable in urine
- How long a drug is detectable in blood
- The basic timeline withdrawal for each drug
Let’s take a look at the facts.
How Long Common Drugs of Misuse Stay in Your Body
(And Withdrawal/Detox Timeline)
- Opioids: For most opioids, withdrawal begins 6-12 hours after the last dose and lasts 4-10 days. Longer acting opioids like methadone may involve withdrawal periods of up to 3 weeks.
- Codeine: 1 day in urine and up to 12 hours in blood
- Heroin: 3-4 days in urine and up to 12 hours in blood
- Methadone: 3-4 days in urine and 24-36 hours in blood
- Morphine: 2-3 days in urine and 6-8 hours in blood
- Fentanyl: 2-3 days in urine and 5-48 hours in blood
- Oxycodone/oxycontin: 4 days in urine and 24 hours in blood
- Cocaine: 3-4 days in urine and 1-2 days in blood. Withdrawal begins quickly and lasts 7-10 days.
- Amphetamine: 1-3 days in urine and around 12 hours in blood. Withdrawal begins 6-12 hours after the last dose and lasts about 7 days.
- Methamphetamine: 3-6 days in urine and 24 – 72 hours in blood. Withdrawal begins 6-12 hours after the last dose and may last as long as a month.
- Marijuana: 7-30 days in urine and up to 2 weeks in blood. Withdrawal from marijuana is nearly as intense as other drugs, but mild psychological and physical discomfort may last for about a week.
- Alcohol: 3-5 days in urine, 10-12 hours in blood. Withdrawal begins about 8 hours after the last drink and lasts 7-10 days.
- Benzodiazepines (Xanax): 3-6 weeks in urine and 2-3 days in blood. Withdrawal typically begins with 1-2 days and may last as long as 6 months to a year.
- MDMA (ecstasy): 3-4 days in urine and 1-2 days in blood. Withdrawal from MDMA has not been studied extensively, but generally follows a timeline similar to amphetamines. Symptoms can begin within 6-12 hours and may last for 3-5 days.
- LSD: 1-3 days in urine and up to 2-3 hours in blood. LSD does not have a withdrawal syndrome like most drugs of misuse. A person who stops taking LSD will lose any tolerance for the drug within 3 days.
- Barbiturates (Seconal, Phenobarbital): 2-4 days in urine and 1-2 days in blood. Withdrawal begins within 24 hours, the most severe symptoms occur within 72 hours, and may last for up to three weeks.
Some drugs – primarily benzodiazepines – cause a withdrawal phenomenon called post-acute withdrawal syndrome (PAWS). PAWS occurs when symptoms of withdrawal may last for several months. In some cases, the symptoms may persist for years. The most common PAWS symptom is insomnia. However, symptoms such as irritability, fatigue, depression, cravings, anhedonia (inability to feel pleasure), decreased libido, impulse control, and problems with memory and/or concentration can persist for months. Or, as mentioned, some of these symptoms may persist for a year or more, in rare cases.
Medication: Use Only as Directed
There are many reasons to use medication only as directed, and no real good reason to use a medication in a way other than directed by a physician. The most important reason to follow directions is your health. The people who research, design, manufacture, and sell medications can’t do any of the above if the medication creates a health or safety risk.
That’s why every medication – especially prescription medication – comes with that extra piece of paper that includes basic dosage guidance, abundant warnings about drug interactions, and an extensive list of dos and don’ts: do take this medication with food, don’t take double if you miss a does, don’t take this medication before driving or operating heavy machinery, do call your doctor if you experience these side effects – all that information is there for one reason: your health and safety.
We provide the information above for the same reason. It’s for the health and safety of our patients, who need to know how long drugs stay in their body in order to understand the potential risks and benefits of any medication they take during recovery, which includes how long a drug might stay in their system.
About The Author
