Methadone Injection

Brand Name(s): ; also available generically

IMPORTANT WARNING: Methadone injection may be habit forming. Use methadone injection exactly as directed. Do not use a larger dose, take it more often, or use it for a longer period of time or in a different way than prescribed by your doctor. While using methadone injection, discuss with your healthcare provider your pain treatment goals, length of treatment, and other ways to manage your pain. Tell your doctor if you or anyone in your family drinks or has ever drunk large amounts of alcohol, uses or has ever used street drugs, or has overused prescription medications, or has had an overdose, or if you have or have ever had depression or another mental illness. There is a greater risk that you will overuse methadone injection if you have or have ever had any of these conditions. Talk to your healthcare provider immediately and ask for guidance if you think that you have an opioid addiction or call the U.S. Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-HELP. Methadone injection may cause serious or life-threatening breathing problems, especially during the first 24 to 72 hours of your treatment and any time your dose is increased. Your doctor will monitor you carefully during your treatment. Tell your doctor if you have or have ever had slowed breathing or asthma. Your doctor will probably tell you not to use methadone injection. Also tell your doctor if you have or have ever had lung disease such as chronic obstructive pulmonary disease (COPD; a group of lung diseases that includes chronic bronchitis and emphysema), a head injury, a brain tumor, or any condition that increases the amount of pressure in your brain. The risk that you will develop breathing problems may be higher if you are an older adult or are weak or malnourished due to disease. If you experience any of the following symptoms, call your doctor or get emergency medical treatment: slowed breathing, long pauses between breaths, or shortness of breath. Taking certain other medications during your treatment with methadone injection may increase the risk that you will experience serious, life-threatening side effects such as breathing problems, sedation, or coma. Tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take. Your doctor may need to change the doses of your medications and will monitor you carefully. If you use methadone injection with other medications and you develop any of the following symptoms, call your doctor immediately or seek emergency medical care: unusual dizziness, lightheadedness, extreme sleepiness, slowed or difficult breathing, or unresponsiveness. Be sure that your caregiver or family members know which symptoms may be serious so they can call the doctor or emergency medical care if you are unable to seek treatment on your own. Drinking alcohol, taking prescription or nonprescription medications that contain alcohol, or using street drugs during your treatment with methadone injection increases the risk that you will experience serious, life-threatening side effects. Do not drink alcohol, take prescription or nonprescription medications that contain alcohol, or use street drugs during your treatment. Do not allow anyone else to use your medication. Methadone injection may harm or cause death to other people who take your medication, especially children. Store methadone injection in a safe place so that no one else can take it accidentally or on purpose. Be especially careful to keep methadone injection out of the reach of children. Keep track of how much liquid is left so you will know if any medication is missing. Dispose of any unwanted methadone injection properly according to instructions. (See STORAGE and DISPOSAL.) Methadone injection may cause QT prolongation (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death). Tell your doctor if you or anyone in your family has or has ever had long QT syndrome (an inherited condition in which a person is more likely to have QT prolongation) or if you have or ever had a slow or irregular heartbeat, low blood levels of potassium or magnesium, or heart disease. Some medications when taken with methadone injection may increase the risk of QT prolongation occurring. Be sure and tell your doctor and pharmacist what medications you are taking before starting methadone. If you experience any of the following symptoms, call your doctor immediately: pounding heartbeat, dizziness, lightheadedness, or fainting. Tell your doctor if you are pregnant or plan to become pregnant. If you use methadone injection regularly during your pregnancy, your baby may experience life-threatening withdrawal symptoms after birth. Tell your baby's doctor right away if your baby experiences any of the following symptoms: irritability, hyperactivity, abnormal sleep, high-pitched cry, uncontrollable shaking of a part of the body, vomiting, diarrhea, or failure to gain weight. Talk to your doctor about the risks of using methadone injection for your condition. Use of methadone to treat opiate addiction: If you have been addicted to an opiate (narcotic drug such as heroin), and you are using methadone injection to help you stop taking or continue not taking the drug, you must enroll in a treatment program. The treatment program must be approved by the state and federal governments and must treat patients according to specific federal laws. You may have to take your medication at the treatment program facility under the supervision of the program staff. Ask your doctor or the treatment program staff if you have any questions about enrolling in the program or taking or getting your medication.

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.

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.

Are there OTHER USES for this medicine?

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

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.
• if you are having surgery, including dental surgery, tell the doctor or dentist that you are 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.

What SPECIAL DIETARY instructions should I follow?

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

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 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 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.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS^® Patient Medication Information™. © Copyright, 2024. The American Society of Health-System Pharmacists^®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: March 15, 2024.

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