Naltrexone blocks the effects of opioid medication, including pain relief or feelings of well-being that can lead to opioid abuse. An opioid is sometimes called a narcotic. Naltrexone is used as part of a treatment program for drug or alcohol dependence.
Naltrexone is used to prevent relapse in people who became dependent on opioid medicine and then stopped using it. Naltrexone can help keep you from feeling a “need” to use the opioid.
Naltrexone is also used to treat alcoholism by reducing your urge to drink alcohol. This may help you drink less or stop drinking completely. Naltrexone will not cause you to “sober up” and will not decrease the effects of alcohol you recently consumed.
Naltrexone is not a cure for drug addiction or alcoholism.
Abdominal or stomach pain (severe)
blurred vision, aching, burning, or swollen eyes
discomfort while urinating or frequent urination
hallucinations or seeing, hearing, or feeling things that are not there
mental depression or other mood or mental changes
ringing or buzzing in the ears
shortness of breath
swelling of the face, feet, or lower legs
Some naltrexone side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:
Abdominal or stomach cramping or pain (mild or moderate)
anxiety, nervousness, restlessness or trouble sleeping
joint or muscle pain
nausea or vomiting
cough, hoarseness, runny or stuffy nose, sinus problems, sneezing, or sore throat
fast or pounding heartbeat
loss of appetite
sexual problems in males
(oral tablet, compounding powder, intramuscular powder for injection, extended release)