Vivitrol Side Effects
Overall, Vivitrol is well tolerated. Little difference exists in the side effect profile between the injectable and oral formulations of naltrexone.
However, the medication does carry some risk of side effects. Some common side effects associated with Vivitrol use are:
- Nausea
- Vomiting
- Headache
- Dizziness
- Painful joints and/or muscle cramps
- Insomnia (difficulty sleeping)
- Pain at the injection site
- Tiredness or lethargy (do not operate heavy machinery or drive while taking this medication
There are also some rare, serious side effects of Vivitrol, including:
- Serious allergic reaction, also called hypersensitivity, may occur directly after injection. Tell your doctor if you experience severe rash, swelling of the face or mouth, trouble breathing, wheezing or chest pain.
- Eosinophilic (Allergic) pneumonia
- Depressed mood
- Injection-site reaction, such as infection or abscess
The active ingredient in Vivitrol, naltrexone, can cause liver damage (hepatotoxicity) in some users. Although this may not be the case for Vivitrol, if signs of liver toxicity do develop (stomach pain, dark urine, yellowing of the eyes), contact your health care provider immediately.
Vivitrol and Pregnancy
While it is not known if Vivitrol is specifically harmful to a pregnant mother or her unborn baby, the active ingredient within it, called naltrexone, is harmful. Naltrexone is classified as a Category C medication, meaning it was shown to produce damaging effects in animal studies. As of now, there are no equivalent studies in humans.
Naltrexone use during pregnancy is a delicate matter. While naltrexone has potential in the treatment of opioid-dependent pregnant women, its current uses are limited, as little data exists on its safety profile.
What is well known, however, is the direct adverse effects of opioids, such as heroin, on a developing infant. Opioid and alcohol use during pregnancy should be strictly avoided.
If someone becomes pregnant while prescribed naltrexone, they should discontinue taking the medication if the risk of opioid-relapse is low. If the risk of relapse is believed to be high, some people, teamed up with their physician, may decide to continue naltrexone. In this case, the good may outweigh the bad. Some studies have demonstrated favorable outcomes using naltrexone in heavy opioid users. Naltrexone may provide some heavy users the support needed to ensure an opioid-free pregnancy, and as a result, a healthy baby.
Additionally, naltrexone and its metabolites are found in breast milk, a consideration all breast-feeding mothers should discuss with their health care providers.
It is important to consult your health care provider if you become pregnant while taking naltrexone.