Medical Editor: John P. Cunha, DO, FACOEP
Naltrexone Hydrochloride Tablets are an opioid antagonist indicated in the treatment of alcohol dependence and for the blockade of the effects of exogenously administered opioids. Naltrexone Hydrochloride tablets are available in generic form. Common side effects of Naltrexone Hydrochloride include:
- anxiety, and
Naltrexone Hydrochloride may cause:
- suicidal ideation, and
- suicidal attempts.
Tell your doctor if this occurs.
Before stating Naltrexone Hydrochloride, an opioid-free interval of a minimum of 7 to 10 days is recommended for patients previously dependent on short-acting opioids. To treat alcoholism, a dose of 50 mg Naltrexone Hydrochloride once daily is recommended for most patients. For opioid dependence, treatment should be initiated with an initial dose of 25 mg of Naltrexone Hydrochloride tablets. Naltrexone Hydrochloride may interact with thioridazine, opioid containing medicines (such as cough and cold preparations, antidiarrheal preparations, and opioid analgesics), and other drugs. Tell your doctor all medications and supplements you use. Tell your doctor if you are pregnant or plan to become pregnant before using Naltrexone Hydrochloride; it is unknown how it will affect a fetus. It is unknown if Naltrexone Hydrochloride passes into breast milk. Consult your doctor before breastfeeding.
Our Naltrexone Hydrochloride Tablets Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
During two randomized, double-blind placebo-controlled 12-week trials to evaluate the efficacy of naltrexone hydrochloride as an adjunctive treatment of alcohol dependence, most patients tolerated naltrexone hydrochloride well. In these studies, a total of 93 patients received naltrexone hydrochloride at a dose of 50 mg once daily. Five of these patients discontinued naltrexone hydrochloride because of nausea. No serious adverse events were reported during these two trials.
While extensive clinical studies evaluating the use of naltrexone hydrochloride in detoxified, formerly opioid-dependent individuals failed to identify any single, serious untoward risk of naltrexone hydrochloride use, placebo-controlled studies employing up to five fold higher doses of naltrexone hydrochloride (up to 300 mg per day) than that recommended for use in opiate receptor blockade have shown that naltrexone hydrochloride causes hepatocellular injury in a substantial proportion of patients exposed at higher doses (see WARNINGS and PRECAUTIONS, Laboratory Tests).
Aside from this finding, and the risk of precipitated opioid withdrawal, available evidence does not incriminate naltrexone hydrochloride, used at any dose, as a cause of any other serious adverse reaction for the patient who is “opioid-free.” It is critical to recognize that naltrexone hydrochloride can precipitate or exacerbate abstinence signs and symptoms in any individual who is not completely free of exogenous opioids.
Patients with addictive disorders, especially opioid addiction, are at risk for multiple numerous adverse events and abnormal laboratory findings, including liver function abnormalities. Data from both controlled and observational studies suggest that these abnormalities, other than the dose-related hepatotoxicity described above, are not related to the use of naltrexone hydrochloride.
Among opioid-free individuals, naltrexone hydrochloride administration at the recommended dose has not been associated with a predictable profile of serious adverse or untoward events. However, as mentioned above, among individuals using opioids, naltrexone hydrochloride may cause serious withdrawal reactions (see CONTRAINDICATIONS, WARNINGS, and DOSAGE AND ADMINISTRATION).
Reported Adverse Events
Naltrexone hydrochloride has not been shown to cause significant increases in complaints in placebocontrolled trials in patients known to be free of opioids for more than 7 to 10 days. Studies in alcoholic populations and in volunteers in clinical pharmacology studies have suggested that a small fraction of patients may experience an opioid withdrawal-like symptom complex consisting of tearfulness, mild nausea, abdominal cramps, restlessness, bone or joint pain, myalgia, and nasal symptoms. This may represent the unmasking of occult opioid use, or it may represent symptoms attributable to naltrexone. A number of alternative dosing patterns have been recommended to try to reduce the frequency of these complaints.
In an open label safety study with approximately 570 individuals with alcoholism receiving naltrexone hydrochloride, the following new-onset adverse reactions occurred in 2% or more of the patients: nausea (10%), headache (7%), dizziness (4%), nervousness (4%), fatigue (4%), insomnia (3%), vomiting (3%), anxiety (2%) and somnolence (2%).
Depression, suicidal ideation, and suicidal attempts have been reported in all groups when comparing naltrexone, placebo, or controls undergoing treatment for alcoholism.
|RATE RANGES OF NEW ONSET EVENTS|
|Depression||0 to 15%||0 to 17%|
|Suicide Attempt/Ideation||0 to 1%||0 to 3%|
Although no causal relationship with naltrexone hydrochloride is suspected, physicians should be aware that treatment with naltrexone hydrochloride does not reduce the risk of suicide in these patients (see PRECAUTIONS).
The following adverse reactions have been reported both at baseline and during the naltrexone hydrochloride clinical trials in opioid addiction at an incidence rate of more than 10%:
Difficulty sleeping, anxiety, nervousness, abdominal pain/cramps, nausea and/or vomiting, low energy, joint and muscle pain, and headache.
The Incidence Was Less Than 10% For
The Following Events Occurred In Less Than 1% Of Subjects
Gastrointestinal: Excessive gas, hemorrhoids, diarrhea, ulcer.
Genitourinary: Increased frequency of, or discomfort during, urination; increased or decreased sexual interest.
Special senses: Eyes blurred, burning, light sensitive, swollen, aching, strained; ears- “clogged”, aching, tinnitus.
Data collected from postmarketing use of naltrexone hydrochloride show that most events usually occur early in the course of drug therapy and are transient. It is not always possible to distinguish these occurrences from those signs and symptoms that may result from a withdrawal syndrome. Events that have been reported include anorexia, asthenia, chest pain, fatigue, headache, hot flushes, malaise, changes in blood pressure, agitation, dizziness, hyperkinesia, nausea, vomiting, tremor, abdominal pain, diarrhea, palpitations, myalgia, anxiety, confusion, euphoria, hallucinations, insomnia, nervousness, somnolence, abnormal thinking, dyspnea, rash, increased sweating, vision abnormalities and idiopathic thrombocytopenic purpura.
In some individuals the use of opioid antagonists has been associated with a change in baseline levels of some hypothalamic, pituitary, adrenal, or gonadal hormones. The clinical significance of such changes is not fully understood.
Adverse events, including withdrawal symptoms and death, have been reported with the use of naltrexone hydrochloride in ultra rapid opiate detoxification programs. The cause of death in these cases is not known (see WARNINGS).
In a placebo controlled study in which naltrexone hydrochloride was administered to obese subjects at a dose approximately five-fold that recommended for the blockade of opiate receptors (300 mg per day), 19% (5/26) of naltrexone hydrochloride recipients and 0% (0/24) of placebo-treated patients developed elevations of serum transaminases (i.e., peak ALT values ranging from 121 to 532; or 3 to 19 times their baseline values) after three to eight weeks of treatment. The patients involved were generally clinically asymptomatic, and the transaminase levels of all patients on whom follow-up was obtained returned to (or toward) baseline values in a matter of weeks.
Transaminase elevations were also observed in other placebo controlled studies in which exposure to naltrexone hydrochloride at doses above the amount recommended for the treatment of alcoholism or opioid blockade consistently produced more numerous and more significant elevations of serum transaminases than did placebo. Transaminase elevations occurred in 3 of 9 patients with Alzheimer's Disease who received naltrexone hydrochloride (at doses up to 300 mg/day) for 5 to 8 weeks in an open clinical trial.
Read the entire FDA prescribing information for Naltrexone Hydrochloride (naltrexone hydrochloride)