• Methadone is a substitute for street drugs like heroin which cause addiction.
  • It is important for you to continue to take methadone regularly to reduce the risk of withdrawal symptoms occurring.
  • You are more likely to succeed in staying off heroin if you have support. Ask about the counselling and help available in your area.

About methadone

Type of medicine Opioid substitution therapy
Used for To manage opioid dependence, such as heroin addiction
Available as Oral liquid

Methadone is used to help you keep off street drugs such as heroin. It can prevent or reduce the unpleasant withdrawal symptoms when you stop using such drugs. It is a medicine that is similar to heroin and works as a replacement treatment. Many people choose to stay on methadone long-term, although some people gradually reduce their dose and come off it.

The effects of methadone last longer than heroin so it is usually prescribed as a once-daily dose. To begin with, you will usually be asked to take it under the supervision of the pharmacist who dispenses the methadone to you. This means there can be no doubt about how much methadone you take at each dose. This supervision may be relaxed after a few months of your taking a regular maintenance dose.

Methadone also acts as a painkiller. It is occasionally used to treat severe pain if other strong painkillers are unsuitable. If you have been prescribed methadone for this reason, then you should ask your doctor or home-care team if you have any questions about your treatment. This medicine leaflet gives information about methadone when it is used to manage drug addiction only.

Before taking methadone

To make sure this is the right treatment for you, before you start using methadone it is important that your doctor or pharmacist knows:

  • If you are pregnant or breast-feeding.
  • If you have liver, kidney, heart or prostate problems.
  • If you have breathing problems, such as asthma or chronic obstructive pulmonary disease (COPD).
  • If you have low blood pressure.
  • If you have thyroid problems.
  • If you have fits or epilepsy.
  • If you have a problem in your bile duct.
  • If you have an inflammatory bowel problem.
  • If you have myasthenia gravis (a condition causing muscle weakness).
  • If you have recently suffered a serious head injury.
  • If you have adrenal gland problems or phaeochromocytoma (a growth on your adrenal glands).
  • If you have ever had an allergic reaction to any medicine.
  • If you are taking any other medicines, including those available to buy without a prescription, herbal and complementary medicines.

How to take methadone

  • Follow the advice your doctor has given you carefully, and read any printed information you have been given. The manufacturer's printed information leaflet will give you more information about methadone, and a full list of possible side-effects from taking it.
  • Take methadone exactly as your doctor has told you. Do not take more or less than the dose you have been prescribed.
  • Try to take your methadone dose at the same time each day. Initially you will be asked to take methadone where you can be supervised. This is to help you stick with your treatment and make sure you do not miss any doses.
  • At first your doctor will prescribe a low-ish dose, and then see you frequently to adjust this to a regular maintenance dose. This early stage is very important because too high a dose can cause you serious harm, so please be patient. It may take a few weeks until the correct dose is found, and you may have some withdrawal symptoms during this time. The correct dose varies from person to person depending on how much heroin you were using and how your body deals with (metabolises) methadone.
  • If you forget to take a dose, wait until your next dose is due and then take only one dose. Do not take two doses together to make up for a missed dose.
  • It is important that your doctor knows if you have not taken any doses. This is because if you miss more than three days of methadone, your dose will need to be changed.

Getting the most from your treatment

  • It is important that you keep your regular appointments with your doctor or clinic so your progress can be reviewed. You will be asked to give a urine sample from time to time.
  • Methadone causes drowsiness and will affect your ability to drive. You should tell the DVLA that you are taking methadone if you are a driver. You are likely to be banned from driving at first, although you may be allowed to drive again later, subject to an annual medical review. Your doctor will tell you when you can resume driving.
  • Do not take more than the dose your doctor has prescribed for you. Signs of overdose can include pinpoint pupils, shallow breathing and eventually unconsciousness. If you suspect that you or someone else might have had an overdose of methadone, contact your doctor or go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.
  • You are more likely to succeed in staying off heroin if you have support and counselling. Local drug community teams, self-help groups and other agencies may be of help. It is much harder to 'do it alone', so go for counselling and help if it is available in your area.
  • You should not take any street drugs or drink too much alcohol while you are on methadone. This is because other street drugs such as benzodiazepines ('benzos'), and alcohol can affect methadone and increase the chance of unwanted effects.
  • Methadone (even in small amounts) is a special hazard to children and other people if it is swallowed by accident. If you suspect that someone else has taken some of this medicine, get medical help straightaway.
  • Do not stop taking methadone without discussing this with your doctor or drug-team worker first. It is important that methadone should be taken regularly to reduce the risk of withdrawal symptoms occurring. Withdrawal symptoms from methadone are similar to those from heroin (they are less severe, but last longer). When you are ready to consider becoming drug-free, your doctor or drug-team worker will be able to help you decide on the best way to do this in order to keep withdrawal effects to a minimum.
  • If you buy any medicines, check with a pharmacist that they are safe to take with methadone.
  • If you are having an operation or dental treatment, tell the person carrying out the treatment that you are taking methadone.

Can methadone cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. Speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

Common methadone side-effects - these affect around 1 in 10 people who take this medicine What can I do if I experience this?
Feeling or being sick, abdominal pain Stick to simple meals - avoid rich or spicy foods
Constipation Eat a well-balanced diet and drink plenty of water each day
Feeling dizzy, faint or sleepy Do not drive or use tools or machines. Do not drink alcohol
Dry mouth Try chewing sugar-free gum or sucking sugar-free sweets
Other common effects include: fluid retention causing swollen feet or ankles, mood changes, vertigo (a spinning sensation), increased weight, eyesight problems, sweating, and skin rash If any of these become particularly troublesome, speak with your doctor

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

How to store methadone

  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.