Morphine / naltrexone Side Effects
Medically reviewed by Drugs.com. Last updated on Sep 17, 2023.
Applies to morphine / naltrexone: oral capsule extended release.
- This drug is a strong pain drug that can put you at risk for addiction, abuse, and misuse. Misuse or abuse of this drug can lead to overdose and death. Talk with your doctor.
- You will be watched closely to make sure you do not misuse, abuse, or become addicted to this drug.
- Even one dose of this drug may be deadly if it is taken by someone else or by accident, especially in children. If this drug 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.
- This drug 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 this drug or anytime your dose is raised.
- Swallow whole. Do not chew, break, crush, or dissolve before swallowing. Doing these things can cause very bad side effects and death.
- If you cannot swallow this drug whole, you may sprinkle the contents on applesauce. If you do this, swallow the mixture right away without chewing.
- This drug 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 this drug 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 this drug 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.
- Using this drug for a long time during pregnancy may lead to withdrawal in the newborn baby. This can be life-threatening. Talk with the doctor.
Serious side effects
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.
- Trouble breathing, slow breathing, or shallow breathing.
- Shortness of breath.
- Very bad dizziness or passing out.
- Very upset stomach or throwing up.
- Very bad constipation.
- Chest pain or pressure or a fast heartbeat.
- Feeling very sleepy.
- Noisy breathing.
- Feeling confused.
- Very bad belly pain.
- 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).
- A severe and sometimes deadly problem called serotonin syndrome may happen if you take this drug 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.
- Taking an opioid drug like this drug 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.
Other side effects
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 you have any side effects that bother you or do not go away.
- Feeling sleepy.
- Upset stomach or throwing up.
- Dry mouth.
- Feeling tired or weak.
- Belly pain.
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.
For Healthcare Professionals
Applies to morphine/naltrexone: oral capsule extended release.
The most common adverse events included constipation, nausea, and somnolence.[Ref]
Common (1% to 10%): Insomnia, anxiety, depression, restlessness, irritability
Frequency not reported: Disorientation, abnormal thinking, mental status changes, confusional state, euphoric mood, hallucination, abnormal dreams, mood swings, nervousness[Ref]
Disorientation, abnormal thinking, mental status changes, confusional state, euphoric mood, hallucination, abnormal dreams, mood swings, and nervousness, were reported in less than 1% of patients.[Ref]
Depressed level of consciousness, mental impairment, memory impairment, disturbance in attention stupor, paresthesia, and abnormal coordination, were reported in less than 1% of patients.[Ref]
Very common (10% or more): Somnolence (14%),
Common (1% to 10%): Dizziness, headache, tremor
Frequency not reported: Depressed level of consciousness, mental impairment, memory impairment, disturbance in attention stupor, paresthesia, abnormal coordination[Ref]
Very common (10% or more): Constipation (up to 31%), nausea (up to 22%)
Common (1% to 10%): Vomiting, dry mouth, diarrhea, abdominal pain upper, abdominal pain, dyspepsia, flatulence, stomach discomfort
Abdominal distension, pancreatitis, fecaloma, abdominal tenderness, were reported in less than 1% of patients.[Ref]
Common (1% to 10%): Flushing, peripheral edema
Frequency not reported: Dyspnea, rhinorrhea[Ref]
Dyspnea and rhinorrhea were reported in less than 1% of patients.[Ref]
Cholecystitis, ALT and AST increases were reported in less than 1% of patients.[Ref]
Common (1% to 10%): Anorexia, decreased appetite[Ref]
Common (1% to 10%): Hyperhidrosis, pruritus
Frequency not reported: Rash, piloerection, cold sweat, night sweats[Ref]
Rash, piloerection, cold sweat, and night sweats were reported in less than 1% of patients.[Ref]
Common (1% to 10%): Muscle spasms, arthralgia
Frequency not reported: Myalgia, muscle weakness[Ref]
Myalgia and muscle weakness were reported in less than 1% of patients.[Ref]
Blurred vision was reported in less than 1% of patients.[Ref]
Frequency not reported: Blurred vision[Ref]
Urinary retention and dysuria were reported in less than 1% of patients.[Ref]
Frequency not reported: Urinary retention, dysuria[Ref]
Frequency not reported: Erectile dysfunction[Ref]
Anaphylaxis has been reported with ingredients contained in this product.[Ref]
Common (1% to 10%): Fatigue, chills, lethargy
Frequency not reported: Malaise, asthenia, drug withdrawal syndrome[Ref]
Malaise, asthenia, and drug withdrawal syndrome, were reported in less than 1% of patients.[Ref]
More about morphine / naltrexone
- Check interactions
- Compare alternatives
- Reviews (52)
- Dosage information
- During pregnancy
- Drug class: narcotic analgesic combinations
Related treatment guides
1. Product Information. Embeda (morphine-naltrexone). King Pharmaceuticals Inc. 2009.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Some side effects may not be reported. You may report them to the FDA.