This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.
- It is used to help with the signs of opioid withdrawal.
- If you are allergic to this drug; any part of this drug; 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: Brain blood vessel disease, heart disease, kidney disease, or slow heartbeat.
- If you have electrolyte (like sodium, potassium, phosphate) problems.
- If you have a long QT on ECG.
- If you have had a recent heart attack.
- If you are taking any drugs that can cause a slow heartbeat. There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
- If you are taking any drugs that can cause low blood pressure. There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
This is not a list of all drugs or health problems that interact with this drug.
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 this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
- Tell all of your health care providers that you take this drug. 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 this drug affects you.
- Low blood pressure, slow heartbeat, and passing out have happened with this drug. If you have questions, talk with the doctor.
- 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.
- Check blood pressure and heart rate as the doctor has told you.
- Talk with your doctor before you use alcohol, marijuana or other forms of cannabis, or prescription or OTC drugs that may slow your actions.
- Be careful in hot weather or while being active. Drink lots of fluids to stop fluid loss.
- Do not use more often or for longer than you were told.
- Do not change the dose or stop this drug without talking with the doctor.
- High blood pressure, anxiety, arm or leg pain, chills, diarrhea, trouble sleeping, and sweating a lot have happened when this drug was stopped all of a sudden.
- This drug is not used to keep a drug-free state. People who have stopped taking opioid drugs may have more risk of side effects if they take opioid drugs again. This includes a raised chance of overdose and death. If you have questions, talk with the doctor.
- Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.
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.
- Dizziness or passing out.
- Slow heartbeat.
- A type of abnormal heartbeat (prolonged QT interval) can happen with this drug. Call your doctor right away if you have a fast heartbeat, a heartbeat that does not feel normal, or if you pass out.
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:
- Trouble sleeping.
- Feeling sleepy.
- Dry mouth.
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 your national health agency.
Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take with or without food.
- Drink lots of noncaffeine liquids unless told to drink less liquid by your doctor.
- Do not take naltrexone within 2 hours before or 2 hours after this drug.
- Take a missed dose as soon as you think about it.
- If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
- Store at room temperature in a dry place. Do not store in a bathroom.
- Protect from heat.
- Store in the original container. Do not take out the antimoisture cube or packet.
- 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.
- 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.
- Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, 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.
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