methadone (oral/injection)

What is the most important information I should know about methadone?

What is methadone?

Methadone is an opioid medication.

Methadone is used for around-the-clock treatment of severe pain. This medicine is not for use on an as-needed basis for pain.

Methadone is also used as part of a drug addiction detoxification program. In people addicted to heroin or other narcotic drugs, methadone reduces withdrawal symptoms without causing the "high" associated with the drug addiction.

Methadone is available only from a certified pharmacy.

Methadone may also be used for purposes not listed in this medication guide.

What should I discuss with my healthcare provider before using methadone?

• severe asthma or breathing problems; or
• a blockage in your stomach or intestines.

Tell your doctor if you have ever had:

• heart problems, long QT syndrome (in you or a family member);
• breathing problems, sleep apnea;
• a head injury, brain tumor, or seizures;
• drug or alcohol addiction, or mental illness;
• liver or kidney disease;
• urination problems; or
• problems with your gallbladder, pancreas, or thyroid.

Tell your doctor if you are pregnant. Your dose needs may be different during pregnancy.

If you use opioid medicine during pregnancy, your baby could be born with life-threatening withdrawal symptoms, and may need medical treatment for several weeks. The benefit of treating opioid addiction may outweigh any risks to the baby.

Ask a doctor before using opioid medicine if you are breastfeeding. Tell your doctor if you notice severe drowsiness or slow breathing in the nursing baby.

How should I use methadone?

Follow the directions on your prescription label and read all medication guides or instruction sheets. Never use methadone in larger amounts, or for longer than prescribed. Tell your doctor if you feel an increased urge to use more of this medicine.

Methadone oral is taken by mouth.

Methadone injection is given in a vein.

Measure liquid medicine with the supplied measuring device (not a kitchen spoon).

Dissolve the dispersible tablet in water, orange juice, or other citrus-flavored non-alcoholic beverage. Stir and drink this mixture right away.

Never crush a pill to inhale the powder or inject it into your vein. This could result in death.

You should not stop using methadone suddenly. Ask your doctor before stopping the medicine.

What happens if I miss a dose?

If you take methadone for pain: Take the missed dose as soon as you remember, then take your next dose 8 to 12 hours later.

If you take methadone for drug addiction: Take your missed dose the next day at the regular time. If you miss your doses for longer than 3 days in a row, call your doctor for instructions. You may need to restart methadone at a lower dose.

Do not take two doses at one time.

What happens if I overdose?

Your doctor may recommend you get naloxone (a medicine to reverse an opioid overdose) and keep it with you at all times. A person caring for you can give the naloxone if you stop breathing or don't wake up. Your caregiver must still get emergency medical help and may need to perform CPR (cardiopulmonary resuscitation) on you while waiting for help to arrive.

Anyone can buy naloxone from a pharmacy or local health department. Make sure any person caring for you knows where you keep naloxone and how to use it.

What should I avoid while using methadone?

Grapefruit may interact with methadone and cause side effects. Avoid consuming grapefruit products.

What are the possible side effects of methadone?

Opioid medicine can slow or stop your breathing, and death may occur. A person caring for you should give naloxone and/or seek emergency medical attention if you have slow breathing with long pauses, blue colored lips, or if you are hard to wake up.

• weak or shallow breathing, breathing that stops during sleep;
• severe constipation;
• a light-headed feeling, like you might pass out;
• fast or pounding heartbeats, fluttering in your chest, shortness of breath;
• low cortisol levels --nausea, vomiting, loss of appetite, dizziness, worsening tiredness or weakness; or
• serotonin syndrome --agitation, hallucinations, fever, fast heart rate, muscle stiffness, twitching, loss of coordination, nausea, diarrhea.

Serious breathing problems may be more likely in older adults and people who are debilitated or have wasting syndrome or chronic breathing disorders.

Common side effects may include:

• dizziness, drowsiness;
• nausea, vomiting;
• increased sweating; or
• pain, redness, or swelling where the medicine was injected.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect methadone?

You may have a fatal methadone overdose if you start or stop using certain other medicines. Tell your doctor about all your medications.

• medicine for allergies, asthma, blood pressure, motion sickness, irritable bowel, or overactive bladder;
• other opioid medicines;
• a benzodiazepine sedative like Valium, Klonopin, or Xanax;
• sleep medicine, muscle relaxers, or other drugs that make you drowsy; or
• drugs that affect serotonin, such as antidepressants, stimulants, or medicine for migraines or Parkinson's disease.

This list is not complete. Many drugs may affect methadone, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here.

Where can I get more information?

Your doctor or pharmacist can provide more information about methadone.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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