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Drug Class: Commonly Known As: Category:
Analgesic Adult

Methadone - Side Effects, Precautions, and Contraindications

What side effects can Methadone cause?

Most of these side effects will get better or go away as the body gets used to the medication.

Common side effects include:

  • Dizziness or light-headedness (Rise slowly over several minutes from sitting or lying position).
  • Drowsiness. Do not drive or operate heavy machinery if affected
  • Constipation
  • Nausea or vomiting

Inform your doctor if the side effects above become severe and bothersome.


Rare but serious effects may sometimes occur. Contact the doctor as soon as possible if any of the following are noticed:

  • Allergic reactions: Skin rash, itching, difficulty in breathing, swelling of face, lips, tongue or throat
  • Shallow breathing
  • Severe dizziness or passing out
  • Fast heartbeat
  • Mental alteration
  • Feeling extremely tired or weak
  • Seizures (fits)

Before taking Methadone , what precautions must I follow?

What food or medicine must I avoid when I take Methadone ?

Avoid alcoholic drink.

Avoid taking grapefruit or grapefruit juice while taking this medicine.

  • Updated on 10/2/2017 12:00:00 AM
  • Article contributed by Pharmacy Department KK Women's and Children's Hospital
The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth


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