Methadone Injection Solution

Generic name: Methadone Injection Solution [ METH-a-done ]
Drug class: Opioids (narcotic analgesics)

Medically reviewed by Drugs.com. Last updated on Jan 9, 2023.

Warning

For all uses of this medicine:

This medicine has an opioid drug in it. Opioid drugs can put you at risk for addiction, abuse, and misuse. Misuse or abuse of methadone injection solution can lead to overdose and death. If you have questions, talk with your doctor.
You will be watched closely to make sure you do not misuse, abuse, or become addicted to methadone injection solution.
This medicine may cause very bad and sometimes deadly breathing problems. Call your doctor right away if you have slow, shallow, or trouble breathing.
The chance of very bad and sometimes deadly breathing problems may be greater when you first start methadone injection solution or anytime your dose is raised.
Even one dose of methadone injection solution may be deadly if it is taken by someone else or by accident, especially in children. If methadone injection solution is taken by someone else or by accident, get medical help right away.
Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
A type of abnormal heartbeat (prolonged QT interval) has happened with methadone injection solution. Sometimes, this has led to another type of unsafe abnormal heartbeat (torsades de pointes). Call your doctor right away if you have a fast or abnormal heartbeat, or if you pass out.
Using methadone injection solution for a long time during pregnancy may lead to withdrawal in the newborn baby. This can be life-threatening. Talk with the doctor.
This medicine has an opioid drug in it. Severe side effects have happened when opioid drugs were used with benzodiazepines or other drugs that may make you drowsy or slow your actions. This includes slow or troubled breathing and death. Benzodiazepines include drugs like alprazolam, diazepam, and lorazepam. Benzodiazepines may be used to treat many health problems like anxiety, trouble sleeping, or seizures. If you have questions, talk with your doctor.
Many drugs interact with methadone injection solution and can raise the chance of side effects like deadly breathing problems. Talk with your doctor and pharmacist to make sure it is safe to use methadone injection solution with all of your drugs.
Do not take with alcohol or products that have alcohol. Unsafe and sometimes deadly effects may happen.
Get medical help right away if you feel very sleepy, very dizzy, or if you pass out. Caregivers or others need to get medical help right away if the patient does not respond, does not answer or react like normal, or will not wake up.

Drug addiction:

If you are taking methadone injection solution to treat drug addiction, you must be in a certified care program to get it.

Uses of Methadone Injection Solution:

It is used to ease very bad pain.
It is used to treat addiction problems.
It may be given to you for other reasons. Talk with the doctor.

If taking methadone injection solution for pain:

It is only to be used when around-the-clock (continuous) care is needed for a long time. It is also only to be used when other pain drugs do not treat your pain well enough or you cannot take them.

What do I need to tell my doctor BEFORE I take Methadone Injection Solution?

If you have an allergy to methadone or any other part of methadone injection solution.
If you are allergic to methadone injection solution; any part of methadone injection solution; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
If you have any of these health problems: Lung or breathing problems like asthma, trouble breathing, or sleep apnea; high levels of carbon dioxide in the blood; or stomach or bowel block or narrowing.
If you have taken certain drugs for depression or Parkinson's disease in the last 14 days. This includes isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline. Very high blood pressure may happen.
If you are taking any of these drugs: Linezolid or methylene blue.
If you are taking any of these drugs: Buprenorphine, butorphanol, nalbuphine, or pentazocine.

This is not a list of all drugs or health problems that interact with methadone injection solution.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take methadone injection solution with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Methadone Injection Solution?

Tell all of your health care providers that you take methadone injection solution. This includes your doctors, nurses, pharmacists, and dentists.
Avoid driving and doing other tasks or actions that call for you to be alert until you see how methadone injection solution affects you.
To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs.
This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take methadone injection solution.
Do not take methadone injection solution with other strong pain drugs or if you are using a pain patch without talking to your doctor first.
Do not take more than what your doctor told you to take. Taking more than you are told may raise your chance of very bad side effects.
If you have been taking methadone injection solution for a long time or at high doses, it may not work as well and you may need higher doses to get the same effect. This is known as tolerance. Call your doctor if methadone injection solution stops working well. Do not take more than ordered.
Long-term or regular use of opioid drugs like methadone injection solution may lead to dependence. Lowering the dose or stopping methadone injection solution all of a sudden may cause a greater risk of withdrawal or other severe problems. Talk to your doctor before you lower the dose or stop methadone injection solution. You will need to follow your doctor’s instructions. Tell your doctor if you have more pain, mood changes, thoughts of suicide, or any other bad effects.
This medicine may raise the chance of seizures in some people, including people who have had seizures in the past. Talk to your doctor to see if you have a greater chance of seizures while taking methadone injection solution.
Long-term use of an opioid drug may lead to lower sex hormone levels. Call your doctor if you have a lowered interest in sex, fertility problems, no menstrual period (women), or change in sex ability (men).
Taking an opioid drug like methadone injection solution may lead to a rare but very bad adrenal gland problem. Call your doctor right away if you have very bad dizziness or passing out, very bad upset stomach or throwing up, or if you feel less hungry, very tired, or very weak.
If you are 65 or older, use methadone injection solution with care. You could have more side effects.
This medicine may cause harm to the unborn baby if you take it while you are pregnant. If you are pregnant or you get pregnant while taking methadone injection solution, call your doctor right away.
Tell your doctor if you are breast-feeding or plan to breast-feed. This medicine passes into breast milk and may harm your baby.

How is this medicine (Methadone Injection Solution) best taken?

Use methadone injection solution as ordered by your doctor. Read all information given to you. Follow all instructions closely.

For all uses of methadone injection solution:

It is given as a shot into a muscle, vein, or into the fatty part of the skin.

Drug addiction:

You may need to go to a clinic for your dose.

What do I do if I miss a dose?

Call your doctor to find out what to do.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
Signs of low potassium levels like muscle pain or weakness, muscle cramps, or a heartbeat that does not feel normal.
Signs of low magnesium levels like mood changes, muscle pain or weakness, muscle cramps or spasms, seizures, shakiness, not hungry, very bad upset stomach or throwing up, or a heartbeat that does not feel normal.
Very bad dizziness or passing out.
Chest pain or pressure.
Slow heartbeat.
Feeling confused.
Very bad constipation.
Feeling very tired or weak.
Hallucinations (seeing or hearing things that are not there).
Mood changes.
Seizures.
Very bad belly pain.
Very bad headache.
Shortness of breath, a big weight gain, or swelling in the arms or legs.
Not able to sleep.
Trouble passing urine.
Any unexplained bruising or bleeding.
Change in eyesight.
Feeling very sleepy.
A severe and sometimes deadly problem called serotonin syndrome may happen if you take methadone injection solution with certain other drugs. Call your doctor right away if you have agitation; change in balance; confusion; hallucinations; fever; fast or abnormal heartbeat; flushing; muscle twitching or stiffness; seizures; shivering or shaking; sweating a lot; severe diarrhea, upset stomach, or throwing up; or severe headache.
Very bad irritation where the shot was given.

What are some other side effects of Methadone Injection Solution?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

Upset stomach or throwing up.
Constipation.
Dizziness.
Feeling sleepy.
Headache.
Sweating a lot.
Feeling tired or weak.
Belly pain.
Irritation where the shot is given.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Methadone Injection Solution?

If you need to store methadone injection solution at home, talk with your doctor, nurse, or pharmacist about how to store it.

Consumer Information Use and Disclaimer

If your symptoms or health problems do not get better or if they become worse, call your doctor.
Do not share your drugs with others and do not take anyone else's drugs.
Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
This medicine comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time methadone injection solution is refilled. If you have any questions about methadone injection solution, please talk with the doctor, pharmacist, or other health care provider.
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.