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The molecular structure of methadone
  • Methadone is a prescription only medicine that can be taken orally and is used mainly to treat opioid addiction. Is was initially developed as a painkiller but now it is much more widely used to treat people who have got stuck on heroin or other opioid drugs (such as prescription painkillers). Methadone is a powerful opioid drug, so it has similar effects to drugs like codeine, morphine, and heroin. It lasts much longer in the body than heroin, and therefore it is used to stabilise people currently using heroin (or other opioid drugs) and then help them get off opioid drugs completely.

    Methadone should not be confused with mephedrone, they are completely different drugs. Anyone taking methadone when they are looking for mephedrone risks extreme danger.

  • Methadone usually comes in liquid form that can be swallowed. It is usually a green liquid although there is a blue liquid that is much more concentrated. Methadone also comes as tablets but this preparation is rarely used.

    Methadone is used illicitly, there is a street value for methadone that has been diverted from medicinal use. Most people use it illicitly in the same way as prescribed. As methadone is a powerful opioid drug it is very dangerous for people who are not tolerant to opioid drugs.

  • Methadone is an opioid drug. It mimics the body’s natural pain-killing chemicals, endorphins. Therefore it can relieve pain, cause drowsiness, can cause mild euphoria, slow breathing, slow the bowels causing constipation, and cause other side effects of opioids.

  • Yes. It is mostly used as a substitute medication for people addicted to opioids such as heroin. It is occasionally prescribed as a pain-killer.

  • As an opioid, it mimics the body’s natural pain-killing chemicals, endorphins. Therefore it can relieve pain, cause drowsiness, can cause mild euphoria, slow breathing, slow the bowels causing constipation, and other side effects of opioids. As it takes longer to build up in the body and takes longer to come out of the body it causes much less euphoria than heroin. However, most people report being drowsy, mentally slowed, and often a bit sweaty taking methadone every day.

  • If someone takes an overdose of an opioid drug they can die quickly. This is usually by respiratory depression (slowing the drive and effectiveness of breathing). Anyone not used to opioid drugs would be much more at risk of this. Methadone is often reported as a contributory cause of death in opioid drug related overdoses. It is particular dangerous if mixed with other drugs such as heroin, alcohol, and benzodiazepines.

    The risks of death by overdose increase when many substances are taken together for example alcohol and benzodiazepines which also have effects on breathing (respiration). Methadone decreases control and impairs judgment, making the risk of accidents much higher. This means activities like driving under the influence of methadone are potentially very dangerous. If you are prescribed methadone by your doctor you must inform the DVLA and they have to make a decision whether you are still safe to drive.

  • The risks of depressed breathing caused by methadone may be increased in people with conditions such as muscle weakness (e.g. myasthenia gravis), sleep apnoea, or lung disease/breathing disorders.

  • Methadone is dangerous if mixed with alcohol, benzodiazepines or heroin. Taking methadone with depressant drugs increases the risk of depressing breathing. Additionally, the effects of methadone may be masked if taken with a stimulant, which can lead to an overdose if a lot of the drug is taken and then the stimulant wears off. Certain medications (e.g. some antidepressants) may also interact with methadone to increase sedative effects.

  • One-off or occasional use of methadone is very unlikely to result in the development of depend-ence. However, taking methadone regularly over a sustained period can cause serious physical and psychological addiction. People who become dependent on methadone may become tolerant to the drug’s effects and experience withdrawal symptoms without it. Users may crave the drug and feel unable to cope without it. The longer the drug is taken, the higher and more regular the dose and the stronger the methadone, the higher the risk of dependence.

  • A period of sustained dependence on any drug can be debilitating and prevent people from working and leading an active life. It may also cause mental and physical harm and opioid withdrawal can be very unpleasant.

    Acute withdrawal effects from methadone can be intense, although for many they will be milder than those from heroin. Acute withdrawal effects include shivering, yawning, feeling cold and clammy, goose-bumps on the skin, diarrhoea and vomiting, flu-like symptoms, agitation, anxiety, insomnia and sensitivity to sound/light. Opioid withdrawal symptoms are unpleasant but do not endanger life.

    Potential effects of long term methadone use include constipation, tiredness, sedation. People often have problems with their teeth as methadone reduces your natural saliva which protects the teeth against dental caries.

  • Long-term risks of methadone are low if it is used as prescribed.

  • How much are you taking? How often?

    If taken according to prescription then methadone is very safe.

    Are you taking it with anything else? Mixing drugs is risky.

    Mixing with benzodiazepines and alcohol is potentially very dangerous. Also if other opioid drugs are used, although initially methadone would usually block the effects, eventually you can over-whelm the methadone and accidentally overdose.

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