Methadone - oral

Patient Medicine Information
Why do I need this medicine?
Methadone is used to relieve moderate to severe pain. It is also used to prevent withdrawal symptoms in individuals who are addicted to opiate drugs.
How do I take this medicine?
Take Methadone exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.

You may take Methadone with or without food. Try to take it at the same time each day.

If you are taking the dispersible type of tablet, do not chew or swallow it. Put the dispersible tablet into a glass of fruit juice or water and allow it to dissolve before drinking the solution.

Do not stop taking Methadone unless instructed otherwise, as stopping it suddenly could worsen your condition.
What should I do if I have forgotten to take this medicine?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.

DO NOT double a dose under any circumstances.
When should I not use this medicine?
Alert your doctor if you have any lung disease e.g. asthma, breathing problems or a condition called “paralytic ileus” wherein the bowel does not work properly, as this medicine may not be suitable for you.

Do not take Methadone together or within 2 weeks of taking a type of antidepressant known as MAO inhibitors, e.g. selegiline.
What should I take note of while taking this medicine?
Inform your doctor if you have the following:

- liver disease
- kidney disease
- heart disease
- thyroid disease
- head injury or brain disease
- depression or history of depression
- prostate enlargement or difficulty urinating
- excessive drinking or problems related to drug or alcohol withdrawal

Let your doctor know if you are pregnant or breastfeeding.
What side effects could I experience?
Methadone may cause drowsiness and dizziness. If affected, do not drive or take part in any activity in which you need to be alert.

Other side effects include any of the following: weakness, tiredness, headache, hallucinations, blurred vision, difficulty sleeping, tiredness, anxiety, nervousness, nausea, vomiting, stomach pain, constipation, dry mouth and sweating.

Some side effects my need immediate medical help. Alert your doctor quickly if you experience difficulty in breathing, extreme drowsiness, changes in your heartbeat, severe dizziness or confusion.

Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Do not take Methadone together or within 2 weeks of taking a type of antidepressant known as MAO inhibitors, e.g. selegiline.

Inform your doctor and pharmacist if you are taking any of these medicines:

- medicines for depression e.g. fluvoxamine, fluoxetine
- medicines for the stomach e.g. cimetidine, domperidone, metoclopramide
- medicines for HIV e.g. nevirapine, abacavir, ritonavir
- antibiotics e.g. rifampicin, erythromycin, ciprofloxacin
- medicines for fungal infection e.g. fluconazole, ketoconazole
- medicines for epilepsy (seizures or fits) e.g. phenytoin, carbamazepine, phenobarbital
This list does not include all medicines that may interact with Methadone.

Always notify your doctor and pharmacist if you are taking any other medicines including herbal tonics such as traditional Chinese medicine, supplements and medicines that you buy without a prescription.
What special dietary instructions should I follow?
Avoid alcohol, grapefruit juice and St. John's wort.
How should I store this medicine?
Store in a cool, dry place away from the reach of children.

Medicines must not be used past the expiry date.
This information is independently developed by MIMS based on methadone - oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2021 MIMS. All rights reserved. Powered by
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