Methadone facts

Gail Evans, Alphabiolabs

By Gail Evans, Technical Trainer at AlphaBiolabs
Last reviewed: 13/03/2023

In this article, we take a closer look at methadone, what it is, how it is used, the side effects of methadone use and more.
Table of contents
  • What is methadone?
  • Street names
  • What does methadone look like?
  • How is methadone used?
  • What are the side effects of methadone use?
  • What happens when you use methadone with other drugs?
  • Which legislation covers methadone use?
  • Is methadone used in medicine?
  • How long does it take for methadone to show up in a drug test?
  • Where can I buy a drug test?

What is methadone?

Methadone is a synthetic opioid that is commonly prescribed as a heroin substitute, for people undergoing treatment for heroin addiction/dependency. It is also used to treat moderate to severe pain when around-the-clock pain relief is needed for a long period of time

A patient who is prescribed methadone for heroin addiction will usually have the dosage reduced over time. This can help them reduce their heroin dependency, while preventing acute withdrawal symptoms that are typically experienced when a user stops taking heroin ‘cold turkey’ (e.g. extreme flu-like symptoms including shivering and shaking).

Although it is most often used in the treatment of addiction, methadone can also be used as a powerful painkiller in medical settings.

Street names:

Some of the most common street names for methadone include:

  • Mixture
  • Linctus
  • Physeptone

What does methadone look like?

Methadone usually comes in the form of a green liquid but can also be prescribed in tablet or injectable form.

How is methadone used?

Methadone is usually swallowed in liquid or tablet form. However, it may also be injected.

What are the side effects of methadone use?

Because methadone is used to reduce a person’s craving for opioids such as heroin, it does have some effects that are similar to heroin: albeit, much milder.

In fact, it is designed to block the familiar ‘pleasurable’ sensations that a person might experience while using opioids. This means that if a person being treated with methadone attempts to get ‘high’ by using opioids, methadone will significantly reduce any euphoric effects that they might usually experience.

Despite this however, methadone is still an opioid, meaning that it does have the potential to be abused if used incorrectly. 

Some common side effects of methadone include:

  • Sedation
  • Slower reaction times
  • Dry mouth
  • Muscle weakness
  • Lower blood pressure and reduced body temperature
  • Shorter attention span

In high doses, methadone can cause other adverse effects including nausea and vomiting, sweating, mood changes, and potentially fatal breathing difficulties.

What happens when you use methadone with other drugs?

Below is an overview of the side effects of using methadone alongside other drugs.


Methadone has the potential to heighten the effects of alcohol in some people.

This means that it can be particularly dangerous for people with alcohol dependency to use methadone.

People who drink alcohol while taking methadone put themselves at an increased risk of serious health issues including low blood pressure and respiratory distress. In extreme cases, mixing the two substances can even lead to coma and death.

Benzodiazepines and other sedatives

Sedative medications such as benzodiazepines slow down the functions of the brain and body.

When taken alongside methadone, these substances can cause severe drowsiness, breathing problems, coma, or even death.

Which legislation covers methadone use?

Misuse of Drugs Act 1971

Under UK law, methadone is classified as a Class A drug.

While it is lawful to possess methadone that has been legally prescribed, it is an offence to obtain, ‘give away’ or sell it without a valid prescription.

Possession Up to 7 years in prison, an unlimited fine or both
Supply Up to life in prison, an unlimited fine or both

Drug Driving Road Traffic Act 2015

Drug driving Up to 6 months in prison, an unlimited fine or both
Criminal record
Driving licence endorsement for 11 years
One-year driving ban
Causing death by dangerous driving Up to 14 years in prison

Is methadone used in medicine?

Methadone is available on prescription only, to treat opioid addiction.

While commonly used to help people recover from heroin dependency, it can also be prescribed to aid withdrawal from other opioids including morphine, fentanyl, and codeine.

It can also be used as a painkiller for long-term pain relief.

How long does it take for methadone to show up in a drug test?

The drug testing detection windows for methadone are as follows:

  • Oral fluid (saliva) – up to 48 hours
  • Urine – up to 4 days
  • Hair – up to 12 months (depending on the length of hair available)
  • Nails – up to 12 months (up to 6 months for fingernails and up to 12 months for toenails)

Oral fluid and urine drug testing are known as ‘narrow-window’ forms of testing and can be used to detect drug use from 30 minutes after consumption, up to a few days. This can vary depending on the type of substance and how much was used. 

The rate at which hair and nails grow means that both hair drug testing and nail drug testing can provide a ‘wide-window’ of detection for drugs and their metabolites (up to 12 months).

Where can I buy a drug test?

AlphaBiolabs offers two types of home drug tests, designed to give you peace of mind or enable you to seek support for a friend or loved one who is struggling with substance misuse.

  • Home Urine Drug Test Kit (£18) – this easy-to-use home drug testing kit can detect drugs and their metabolites in a urine sample. The self-contained screening kit includes built-in test strips, allowing you to read the results in just 5 minutes
  • Drug and Alcohol Nail Test (from £99) – this test can detect drug use for a period of up to 12 months prior to samples being collected, with only a sample of fingernail clippings or toenail clippings required. Simply follow the instructions included in your test kit to collect your nail clipping samples and return them to our accredited laboratory for testing

Please be aware that our home drug test kits are for peace of mind only, and the results cannot be used in court. If you require a drug test for official matters, you will need a legally-instructed drug test. 

For confidential advice about which test might best suit your needs, you can also call our Customer Services team on 0333 600 1300 or email

Home drug tests

Explore our range of at-home drug tests.

Gail Evans, AlphaBiolabs

Gail Evans

Technical Trainer at AlphaBiolabs

A professionally-trained forensic scientist, Gail joined AlphaBiolabs in 2012 and holds the role of Technical Trainer.

Her day-to-day responsibilities include delivering in-depth training sessions both internally and externally, covering DNA, drug, and alcohol testing.

Before joining the company, Gail was a practicing forensic scientist with 25 years’ experience working for the Forensic Science Service, attending scenes of crime, and analysing physical and biological material with potential evidential value.

Gail also holds qualifications in chemistry and is a Lead Auditor for the ISO 9001 standard, the international standard for quality management.

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