Methadone Injection

pronounced as (meth' a done)

Why is this medicine prescribed?

Methadone injection is used to relieve severe and persistent pain in people who are expected to need an opioid pain medication around the clock for a long time and who cannot be treated with other medications. Methadone injection should not be used to treat mild or moderate pain, short-term pain, or pain that can be controlled by medication that is taken as needed. Methadone injection also is used to prevent withdrawal symptoms in patients who were addicted to opiate drugs and are enrolled in treatment programs in order to stop taking or continue not taking the drugs and who are unable to take methadone by mouth. Methadone is in a class of medications called opiate (narcotic) analgesics. Methadone works to treat pain by changing the way the brain and nervous system respond to pain. It works to treat people who were addicted to opiate drugs by producing similar effects and preventing withdrawal symptoms in people who have stopped using these drugs.

Are there other uses for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Methadone injection comes as a solution (liquid) to inject subcutaneously (just under the skin), intramuscularly (into a muscle), or intravenously (into a vein). It is usually injected once every 8 to 12 hours. If methadone injection is used to prevent of withdrawal symptoms in patients who were addicted to opiate drugs, it is usually given by a doctor or nurse in a medical facility. Use methadone injection exactly as directed.

Your doctor may change your dose of methadone during your treatment. Your doctor may decrease your dose or tell you to use methadone injection less often as your treatment continues. If you experience pain during your treatment, your doctor may increase your dose or may prescribe an additional medication to control your pain. Talk to your doctor about how you are feeling during your treatment with methadone injection. If you feel that your pain is not controlled or if your pain increases, becomes worse, or if you have new pain or an increased sensitivity to pain while you are using methadone injection, call your doctor. Do not use extra doses of methadone injection or use doses of methadone injection earlier than they are scheduled even if you experience pain.

Do not stop using methadone injection without talking to your doctor. Your doctor will probably want to decrease your dose gradually. If you suddenly stop taking methadone, you may experience withdrawal symptoms such as restlessness, teary eyes, runny nose, yawning, sweating, chills, muscle pain, widened pupils (black circles in the middle of the eyes), irritability, anxiety, backache, joint pain, weakness, stomach cramps, difficulty falling asleep or staying asleep, nausea, decreased appetite, vomiting, or diarrhea.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

What special precautions should I follow?

Before using methadone injection,

  • tell your doctor and pharmacist if you are allergic to methadone, any other medications, or ingredients in methadone injection. Ask your pharmacist for a list of the ingredients.
  • tell your doctor or pharmacist if you are taking the following medications or have stopped taking them within the past two weeks: isocarboxazid (Marplan), linezolid (Zyvox), methylene blue, phenelzine (Nardil), selegiline (Emsam, Zelapar), or tranylcypromine (Parnate).
  • The following nonprescription or herbal products may interact with methadone: St. John's wort and tryptophan. Be sure to let your doctor and pharmacist know that you are taking these medications before you start using methadone injection. Do not start this medication while using methadone injection without discussing it with your healthcare provider.
  • tell your doctor if you have any of the conditions mentioned in the IMPORTANT WARNING section or have or have ever had a blockage in your intestine or paralytic ileus (condition in which digested food does not move through the intestines) or a blockage in the stomach or intestines. Your doctor may tell you that you should not use methadone injection.
  • tell your doctor if you have or have ever had difficulty urinating; an enlarged prostate (a male reproductive gland); adrenal insufficiency (condition in which the adrenal glands do not produce enough of certain hormones needed for important body functions); diabetes; seizures; or thyroid, pancreas, gallbladder, liver, or kidney disease.
  • tell your doctor if you are breastfeeding. If you breastfeed during your treatment with methadone, your baby may receive some methadone in breastmilk. Watch your baby closely for any changes in behavior or breathing, especially when you start using methadone injection. If your baby develops any of these symptoms, call your baby's doctor immediately or get emergency medical help: unusual sleepiness, difficulty breastfeeding, difficulty breathing, or limpness.
  • you should know that this medication may decrease fertility in men and women. Talk to your doctor about the risks of using methadone injection.
  • you should know that this medication may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you.
  • you should know that methadone may cause dizziness when you get up too quickly from a lying position. This is more common when you first start using methadone injection. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.
  • you should know that methadone may cause constipation. Talk to your doctor about changing your diet or using other medications to prevent or treat constipation while you are using methadone injection.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are using methadone injection.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do in case of overdose?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help . If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

While using methadone injection, you should talk to your doctor about having a rescue medication called naloxone readily available (e.g., home, office). Naloxone is used to reverse the life-threatening effects of an overdose. It works by blocking the effects of opiates to relieve dangerous symptoms caused by high levels of opiates in the blood. Your doctor may also prescribe you naloxone if you are living in a household where there are small children or someone who has abused street or prescription drugs. You should make sure that you and your family members, caregivers, or the people who spend time with you know how to recognize an overdose, how to use naloxone, and what to do until emergency medical help arrives. Your doctor or pharmacist will show you and your family members how to use the medication. Ask your pharmacist for the instructions or visit the manufacturer's website to get the instructions. If symptoms of an overdose occur, a friend or family member should give the first dose of naloxone, call 911 immediately, and stay with you and watch you closely until emergency medical help arrives. Your symptoms may return within a few minutes after you receive naloxone. If your symptoms return, the person should give you another dose of naloxone. Additional doses may be given every 2 to 3 minutes, if symptoms return before medical help arrives.

Symptoms of overdose may include:

  • narrowing or widening of the pupils (black circles in the center of the eyes)
  • slow or shallow breathing
  • difficulty breathing
  • sleepiness
  • drowsiness
  • cool, clammy, or blue skin
  • unable to respond or wake up
  • limp muscles
  • slow heartbeat
  • unusual snoring
  • hearing loss

What side effects can this medicine cause?

Methadone may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • lightheadedness
  • dizziness
  • stomach pain
  • weight gain
  • headache
  • sleepiness
  • nausea
  • vomiting
  • sweating
  • difficulty falling asleep or staying asleep
  • flushing
  • dry mouth
  • vision problems
  • pain or redness at injection site

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately or get emergency medical treatment:

  • seizures
  • rash; hives; itching; hoarseness; difficulty breathing or swallowing; or swelling of the face, mouth, tongue or throat
  • extreme drowsiness
  • agitation, hallucinations (seeing things or hearing voices that do not exist), fever, sweating, confusion, fast heartbeat, shivering, severe muscle stiffness or twitching, loss of coordination, or diarrhea
  • nausea, vomiting, loss of appetite, weakness, or dizziness
  • inability to get or keep an erection
  • irregular menstruation
  • decreased sexual desire
  • difficulty urinating

Methadone injection may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( http://www.fda.gov/Safety/MedWatch ) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, out of reach of children, and in a location that is not easily accessible by others, including visitors to the home. Store it at room temperature and away from excess heat and moisture (not in the bathroom). You must immediately dispose of any medication that is outdated or no longer needed through a medicine take-back program. If you do not have a take-back program nearby or one that you can access promptly, flush any methadone injection solution that is outdated or no longer needed down the toilet. Talk to your pharmacist about the proper disposal of your medication.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( http://goo.gl/c4Rm4p ) for more information if you do not have access to a take-back program.

What other information should I know?

Keep all appointments with your doctor or clinic. Your doctor may order certain lab tests to check your response to methadone injection.

Before having any laboratory test (especially those that involve methylene blue), tell your doctor and the laboratory personnel that you are using methadone injection.

This prescription is not refillable. If you continue to experience pain after you finish using methadone injection, call your doctor. If you take this medication on a regular basis, be sure to schedule appointments with your doctor so that you do not run out of medication.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

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