What is methadone?

Methadone is an opioid medicine available on prescription from your doctor.

What is methadone used for?

Methadone is prescribed for the medical treatment of heroin and other opioid dependencies. Methadone can also be prescribed to help manage severe pain cause by certain conditions.

Because of the risks associated with opioid use, methadone should only be used for pain relief in people who are unable to take non-opioid pain-relief medicines, or in circumstances when pain cannot be managed with other options.

How does methadone work?

When methadone is used to replace another opioid, it helps to lessen the effects of withdrawal and reduces the harm associated with opioid drug use. In this way, methadone makes it easier for people to stop their harmful drug use.

Methadone also works to reduce feelings of pain by interrupting the way nerves signal pain between the brain and the body.

Methadone comes in syrup, injection and tablet forms.

What are the possible side effects of taking methadone?

Like all opioid medicines, methadone can cause life-threatening breathing problems. The risk of these is higher:

• when first taking methadone
• after a dosage increase
• if you are older
• if you have an existing lung problem

Other common side effects of methadone include:

• sweating
• difficulty passing urine
• loss of appetite, nausea and vomiting
• abdominal cramps
• constipation
• aching muscles and joints
• irregular periods
• low sex drive
• rashes and itching
• lethargy, mental 'fog' and confusion

Methadone affects everyone differently, and your likelihood of experiencing side effects is based on several factors, including: whether you are a regular user of methadone; whether you take it with other drugs or medicines; your dosage; your weight; and your general health.

If you experience any of these side effects while taking methadone, or you are concerned about your drug use, speak with your doctor.

Always take medicines exactly as prescribed by your doctor.

What are the risks associated with methadone?

Methadone is an opioid medicine and can cause life-threatening breathing problems.

People who take methadone may become dependent on this medicine if they take it regularly, even after a short period of time.

People can also develop tolerance when they take methadone — this means they need to take larger amounts of the opioid to get the same effect. As the dosage increases, so does the risk of side effects.

If you stop taking methadone suddenly, you may experience withdrawal symptoms.

Methadone may make it difficult for you to drive or operate heavy machinery. If you have recently started taking an opioid medication or changed dosage, you may be at higher risk of having an accident.

If you have kidney problems or your kidney function is impaired, your doctor will need to adjust your dosage of methadone.

There are other factors that may limit your use of methadone — for example, if you drink alcohol or take other medicines that can cause drowsiness.

Your doctor is the best person to advise you on whether methadone is the right medicine for you, how much you need and how long to take it for.

If a person is not breathing, or if they are unresponsive, seek help straight away. Call triple zero (000) and ask for an ambulance.

Are there any alternatives to methadone?

Both methadone and buprenorphine are used to help treat opioid dependence or misuse. Your doctor will work with you to decide the best treatment for you.

Everyone’s pain is unique and different pain-relief medicines are used in different circumstances. If you have been prescribed methadone and have concerns or are experiencing side effects, speak with your doctor about other ways you can manage your pain.

If you have chronic (long-term) pain, your doctor might suggest lifestyle changes to help you manage the discomfort. This may include physical fitness and activity pacing, social activities, relaxation techniques and overall health management.

You can find more information here about options for managing chronic pain.

When should I see my doctor?

Always check with your doctor before adjusting your dosage either up or down.

If you stop taking methadone suddenly, you may experience withdrawal symptoms. Your doctor can advise you on the best way to reduce your dosage of methadone to minimise the impact of withdrawal effects.

If you feel you need to increase your dosage, or you experience any unexpected side effects, see your doctor.

How do I dispose of medicines safely?

It's important you dispose of unwanted opioid medicines safely — unused medicines can be returned to any pharmacy. Don't keep unused methadone 'just in case' since this can lead to inappropriate use.

Keep methadone out of reach of children and pets. Never throw medicines into a garbage bin or flush them down the toilet — this is dangerous to others and harmful to the environment.

Resources and support

Asking about your treatment or medication is important to help you understand your options. Here's a guide to questions to ask your pharmacist or doctor before taking a medicine.

See also this list of medicines that contain methadone to read the consumer medicine information (CMI) leaflet for the brand prescribed, or:

• Call 1300 MEDICINE (1300 633 424) to talk about the medicines you are taking for your pain.
• Learn more about prescription opioids on the Choosing Wisely website.
• For answers to your questions and for practical advice, call the Alcohol and Drug Foundation (1300 85 85 84).
• For confidential alcohol and drug counselling, call DirectLine (1800 888 236).