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.

You should not use methadone if you are allergic to it, or if you have:

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

Methadone may cause a life-threatening heart rhythm disorder. Your heart function may need to be checked during treatment.

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.

Use Methadose Sugar-Free (Oral) exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

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.

Call your doctor at once if you have:

• 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.

Do not drink alcohol. Dangerous side effects or death could occur.

Avoid driving or hazardous activity until you know how this medicine will affect you. Dizziness or drowsiness can cause falls, accidents, or severe injuries.

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