How Long Does Methadone Stay in Your System?

Methadone is an opioid analgesic used to treat extreme pain and help overcome an addiction to other opioids.

It can be helpful for pain management after surgery, an injury, or to get someone through a long-term illness.

In cases where a person has grown dependent on opioids like oxycontin, methadone can also help them overcome that addiction. It’s not a cure, but it can be highly effective as part of a thorough treatment plan.

Methadone’s advantage in battling opioid addictions—which have surged during the COVID-19 pandemic—is that it can block the euphoric high a person gets from other narcotics like codeine, heroin, or hydrocodone. However, it still provides enough of an effect to curb cravings and withdrawal. When administered to help with withdrawal, usually, the dosage will be tapered to wean the patient off the substance.

Methadone Half-Life

One thing that’s considered when dosing medications is their half-life. That is the amount of time the active substance takes to reduce by half. For example, if a drug’s half-life is two hours, then a 100 mg dose will halve to 50 mg after 120 minutes. Then two hours later, it will halve again to 25 mg. Usually, a substance will be eliminated from a person’s body after five or six half-lives. Of course, how often a person uses, the dosage amount, their unique chemistry, gender, percentage of body fat, weight, and other factors will influence matters, too.

Methadone has a longer half-life than many other opioids. Remifentanil (sold as Ultiva), for example, is a potent and swift-acting narcotic with a half-life of approximately 30 minutes. Methadone, in contrast, has a half-life of 24–36 hours.

Other opioids have varying half-lives (oxycodone’s is in the neighborhood of three to five hours, for example, and fentanyl’s is around eight to 10 hours). The longer half-life is part of what makes methadone potentially less habit-forming because it’s not so likely to have a person chasing that high. It’s still risky, but it tends to be safer because it doesn’t usually produce the rapid effect and the swift crash as it wears off.

How Long Does Methadone Last?

How long methadone stays in the system varies. Again, body weight, the amount used, personal chemistry—these details factor into elimination time. Piggybacking on chemistry, a person’s pH levels influence its duration, too. A higher urinary pH, for example, decreases methadone excretion. Methadone and its metabolites can be detected often for up to seven days after last use.

Does Methadone Show Up in a Drug Test?

The answer is yes and no. Urine testing is a systematic method of screening for many substances. Immunoassay tests are commonly used, and they work quickly and are relatively inexpensive. However, while they detect morphine, codeine, and heroin, they don’t always detect other opioids, including methadone. If a test registers positive, then another type of test is needed, usually an extended opioid panel that can detect methadone, oxycodone, buprenorphine, and other substances.

Methadone Drug Test Detection Time

In terms of methadone drug tests, there are many ways to screen for the opioid. Hair provides the longest detection window, followed by urine, sweat, saliva (oral fluid), and blood.

Many drugs can be found in urine, usually anywhere from one to three. There are some exceptions. (Urinary pH, the amount used, and so on.)

Blood has a narrower screening window, typically a few hours, but also may be detected for a few days. Blood testing tends to be more costly and labor-intensive, so it’s not a top choice. Methadone can be detected fairly quickly, though, usually in under an hour, since its effects typically kick in after about 30 minutes.

Saliva testing can be better for identifying specific substances, including some opiates, but oral fluid also provides a narrower testing window.

Sweat can show signs of drug use longer than urine can, but it’s not as commonly used.

As stated, hair gives the most extended testing window in that the substance, whatever it may be, will become part of the new growth, and whatever sample is taken can be measured against growth time. (Hair, for example, grows at a rate of about a half-inch a month, so a 1.5-inch sample taken from close to the scalp can give insight into the past 90 days of activity.)