How Long Methadone Stays in Your System

The duration methadone may stay in someone’s system depends on several factors, including someone’s weight, how much they’ve been using, and more.

This page will provide general information on methadone, including the average lengths of time methadone can be detected using various testing methods.

What Is Methadone?

Methadone is a long-acting synthetic opioid often prescribed to treat opioid addiction.

Methadone is an opioid agonist, meaning it binds with opioid receptors the same way opioids of misuse do; however, methadone does not elicit the same euphoric effects as these other drugs. Instead, methadone mitigates withdrawal symptoms and opioid cravings, allowing someone to function in their daily life and focus on the work needed to sustain recovery. It is typically one year before patients will be advised to begin getting off methadone.

When used as part of an addiction recovery plan, methadone is an effective, research-based treatment that can help a person to maintain abstinence from heroin and other opioids.

A single dose of methadone typically has effects for 24-36 hours. Within this period, a person on methadone maintenance therapy must return to the dispensing clinic, doctor, or another facility to get the next dose. Methadone comes in three formats:

  • Tablets: Also called diskettes, they are dissolved in water and then taken orally.
  • Powder: This is also dissolved in water for oral consumption.
  • Liquid: Methadone maintenance clinics most often, if not always, use the liquid format.

Injectable methadone is always illicit. There are no accredited medical facilities or doctors that provide injectable methadone to a recovering individual.

Methadone Side Effects

Methadone side effects may include:

  • Headache.
  • Loss of appetite.
  • Constipation.
  • Weakness.
  • Weight gain.
  • Sweating.
  • Stomach pain.
  • Nausea.
  • Vomiting.

Severe side effects that require medical assistance may include:

  • Seizures.
  • Pounding heartbeat.
  • Fainting.
  • Trouble breathing.
  • Difficult swallowing.
  • Itching, rash, or hives.
  • Hallucinations.
  • Swelling of the throat, mouth, tongue, eyes, or face.

The appearance of side effects, as well as their severity grade, depends in part on physiological factors that are specific to the individual who is receiving methadone maintenance therapy. Since this is a medically managed treatment, if any moderate to severe symptoms emerge, a person should ask the attending methadone clinic or prescribing doctor for assistance. In a serious situation, however, it is necessary to seek emergency help. Methadone is typically a safe medication provided the patient is observing the guidelines for use.

How Does Methadone Replace Opioids?

Methadone locks into the same brain receptors as other opioids, but it is longer-acting than heroin and other drugs. It is also considered much less dangerous.

Since the opioid receptors are activated by the methadone, the body does not go into severe withdrawal. Methadone’s activation of the receptors has the effect of stemming or eliminating cravings for opioids.

Suboxone (buprenorphine) is a partial opioid agonist that works similarly to methadone.

How Long Does Methadone Stay in Your System?

According to Mental Health Daily, several factors are involved in the amount of time methadone remains in the body. These factors include but are not limited to the patient’s:

  • Metabolic rate.
  • Level of liver functioning.
  • Weight.
  • Height.
  • Food intake over the relevant period.

According to reports, the half-life of methadone varies greatly, as follows: 24-36 hours, 13-47 hours, 15-40 hours, and 8-59 hours. Since the widest window is 8-59 hours and encompasses all other possibilities, it is safely considered to be the most accurate (though wide) window. An 8-59-hour methadone half-life translates to 1.83-13.52 days. In other words, a person may retain methadone in the body for anywhere from 1.83-13.52 days. (Note: This day count is based on half-life math, which is not explained in detail here.)

The length of time methadone can be detected through drug screening also depends on the type of sample tested:

 Methadone Withdrawal

Over time, methadone use can cause someone to develop physiological dependence on the substance. Dependence is a natural process of adaptation to an ongoing presence of a drug, characterized by the emergence of withdrawal symptoms when they attempt to quit or reduce their intake. Dependence is not the same as addiction, though it is often one component of it.

Individuals who take methadone as part of a structured recovery plan will likely experience methadone withdrawal if they cease methadone use abruptly.

Methadone Withdrawal Symptoms

Common methadone withdrawal symptoms include:

  • Tiredness
  • Anxiety
  • Restlessness
  • Sweating
  • Nausea
  • Vomiting
  • Cramps
  • Diarrhea
  • Flu-like symptoms (e.g., runny nose)

Getting Off of Methadone

methadone taper assigned by a medical professional or medical detox can mitigate moderate to severe withdrawal symptoms when someone is ready to get off methadone. Typically, patients need more than just detox to remain in long-term recovery from opioid addiction.

Treatment can encompass several levels of care, such as residential treatment or outpatient care. When combined with medications like methadone, behavioral therapy for addiction treatment is effective in helping someone remain sober long after treatment ends.

If you or a loved one struggles with opioid addiction, please call to begin addiction treatment at Laguna Treatment Hospital or learn how to use insurance to pay for rehab and about other payment options.

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