Hepatotoxicity
Taking excessive doses of naltrexone can lead to hepatocellular impairment.
Naltrexone is contraindicated in acute hepatitis and liver failure. The administration of Vivitrol to patients with acute liver disease should be carefully thought out and justified, taking into account the risk of liver function abnormalities. The relationship between a safe dose of naltrexone and a dose that causes hepatic impairment ≤ 5 times.
When used in recommended doses, Vivitrol is not hepatotoxic. Patients should be warned about the risk of liver damage and advise you to seek medical help in case of symptoms of hepatitis.If such symptoms occur, treatment with Vivitrolum should be discontinued.
Eosinophilic pneumonia
In the course of clinical trials, one case of occurrence and one case of suspicion of eosinophilic pneumonia. In both cases, patients required hospitalization, treatment was performed with antibiotics and glucocorticosteroids.
The possibility of developing eosinophilic pneumonia in a patient receiving Vivitrol should be considered and counseling patients when symptoms such as progressive dyspnoea and hypoxia appear, seek medical help immediately.
Physicians should consider the possibility of developing eosinophilic pneumonia in patients resistant to antibiotics.
Hypersensitivity reactions
When taking the drug Vivitrol can develop such side effects as urticaria, angioedema, anaphylaxis. Patients should be warned that if hypersensitivity reactions develop, you should immediately consult a doctor and stop further treatment drug.
An overdose of opioids after trying to overcome their blockade
After opioid detoxification in patients, tolerance to opioids is usually reduced. Vivitrol blocks the effects of exogenous opioids for 28 days, but there have been reports of fatal opioid overdoses in patients who took opioids before the introduction of a new dose of Vivitrol or in the case of missing the next Vivitrol injection.
Patients treated with Vivitrol may be sensitive to lower doses of opioids than before treatment. This can cause potentially life-threatening opioid intoxication (respiratory failure or respiratory arrest, collapse, etc.). Patients should be warned that after the cessation of treatment with Vivitrolum, they may be sensitive to lower doses of opioids.
It is important to remember the decrease in tolerance to opioids at the end of the dosing interval, that is, about a month after the injection of the drug and in the case of missing the next injection. Patients and their families should be warned about hypersensitivity to opioids and the risk of opioid overdose.
Despite the fact that Vivitrol is a strong antagonist of opioid receptors with a long pharmacological effect, the blockade caused by it can be overcome.Patients attempting to overcome this blockade by administering large doses of exogenous opioids risk taking a lethal dose of opioids and endangering their lives. The concentration of opioids in the plasma immediately after they are taken may be sufficient to overcome the competitive blockade of opioid receptors, and as a consequence, the patient can immediately develop a life-threatening opioid intoxication manifested by respiratory depression and collapse. Patients should be aware of the seriousness of the consequences of trying to overcome the blockade of opioid receptors.
Effect of the drug on the duration of labor and labor
The effect of the drug on the duration of labor and delivery is unknown.
Effect of the drug on laboratory blood counts
In patients receiving treatment Vivitrol, there was an increase in the content of eosinophils in the blood, but after several months of treatment the content of eosinophils normalized.
In patients receiving high doses of the drug, a decrease in platelet count was observed on average by 17.8 x 103 / RTI & gt; However, in the course of randomized controlled trials, the effect of Vivitrol on the increase in bleeding is not proven.
In patients with opioid dependence, who received treatment with the drug for 24 weeks, there was a decrease in platelet count by an average of 62.8 x 103 / RTI & gt; In patients in the placebo group, the platelet count decreased on average by 39.9 x 103 / RTI & gt; However, in the course of randomized controlled trials, the effect of Vivitrol on the increase in bleeding is not proven.
The increase in activity of aspartate aminotransferase in the blood during the treatment with Vivitrol was the same as in the treatment with oral naltrexone and was 1.5% compared with 0.9% in the group receiving placebo.
In clinical studies of up to 6 months with the participation of patients with opioid dependence, 89% of patients were diagnosed with hepatitis C, 41% of patients with HIV infection. The study often observed an increase in the activity of "hepatic" enzymes (alanine aminotransferase, aspartate aminotransferase and gamma-glutamyltransferase). These adverse events were more frequent in the group of patients receiving Vivitrol 380 mg than in the placebo group.
Patients with alanine aminotransferase or aspartate aminotransferase activity exceeding the upper limit of the norm more than three times were not included in the study.
In patients treated with Vivitrol, an increase in the activity of transaminases more than 3 times compared with the upper limit of the norm and requiring immediate treatment, was observed more often than in patients receiving placebo. This increase in enzyme activity was observed in 20% of patients treated with Vivitrol, compared with 13% of patients in the placebo group.
The increase in activity of aspartate aminotransferase more than three times compared with the upper limit of the norm was also more frequent in the group of patients treated with Vivitrol (14%), compared with patients in the placebo group (11%).
In patients with opioid dependence treated with Vivitrol, the activity of alanine aminotransferase increased by an average of 61 IU / L, in patients in the placebo group, an average of 48 IU / L.
In patients with opioid dependence treated with Vivitrol, aspartate aminotransferase activity increased by an average of 40 IU / L, in patients in the placebo group, an average of 31 IU / L.
In clinical trials in patients receiving Vivitrol, there was an increase in activity of creatine phosphokinase, usually 1-2 times compared with the upper limit of the norm. A similar increase in the activity of creatine phosphokinase is also observed in the treatment with oral naltrexone.However, there are cases of a 4-fold and even 35-fold increase in the activity of this enzyme in a group of patients receiving oral naltrexone and Vivitrol, respectively.
In 39% of patients with opioid dependence, treated with Vivitrol, there was an increase in activity of creatine phosphokinase above normal values, in the group of patients receiving placebo, an increase in activity of creatine phosphokinase was observed in 32% of patients.
In some cases, in patients receiving placebo, the activity of creatine phosphokinase increased 41.8 times compared with the upper limit of the norm; in the group of patients treated with Vivitrol, cases of increase in the activity of creatine phosphokinase were found to be 22.1 times higher than the upper limit of the norm.
When carrying out some immunoassay tests of urine, false-positive results may appear on a number of drugs, especially opioids. For further information, refer to the specific test instructions.
Warnings and Precautions
Elimination of the Vivitrol blockade
In an emergency situation in the case of patients receiving Vivitrol treatment,The proposed method of pain relief is regional analgesia, sedation with benzodiazepine and the use of non-narcotic analgesics or general anesthesia.
In situations requiring the use of narcotic analgesia, the required dose of opioids may be higher than normal, as a result of which respiratory depression may be deeper and longer.
Preferably the use of a high-speed narcotic analgesic, which reduces the duration of respiratory depression. The amount of analgesic administered should be determined in accordance with the needs of the patient. There may occur receptor-mediated phenomena (eg, facial edema, itching, generalized erythema, or bronchospasm), presumably because of the secretion of histamine.
Regardless of the remedy chosen to eliminate the Vivitrol blockade, the patient should be carefully monitored by appropriate qualified medical personnel in a specially equipped intensive care unit.
Depression and suicidal behavior
During Vivitrol's controlled clinical trials, adverse suicidal events (suicidal thoughts, suicide attempts, committed suicides) were infrequent,however, were found in the group of patients receiving Vivitrol treatment more often than in the group receiving placebo (1% vs. 0). In some cases, suicidal thoughts and behavior appeared in the patient after completion of the study, but were a consequence of the depression that developed during drug treatment. There were two committed suicides, in both cases, patients were treated with Vivitrol.
The discontinuation of the drug, associated with the manifestation of depression, occurred more often in the group of patients taking Vivitrol (1%) than in the placebo group (0).
In a 24-week placebo-controlled study, adverse events associated with depressive moods were observed in 10% of patients treated with Vivitrol at a dose of 380 mg, and in the group receiving placebo injections in 5%.
It should be closely monitored for the appearance of signs of depression or suicidal thoughts in patients with alcohol dependence, including patients receiving Vivitrol treatment. Family members and caregivers should be warned about the need to closely monitor the occurrence of symptoms of depression or suicidal behavior and immediately report the occurrence of such symptoms to the treating physician.
Reactions at the injection site
Injections of Vivitrol may be accompanied by pain, soreness, tightness, swelling, erythema and pruritus. During clinical trials, one patient developed a compaction that, 4 weeks after the injection, continued to increase, followed by the development of necrosis, which required surgical removal for removal. During post-registration observations, other cases of reactions at the injection site, including abscess, sterile abscess, compaction and necrosis, were noted, some of which required surgical intervention. Patients should be warned about the need to inform the attending physician of any reaction at the injection site.
Alcohol withdrawal
The use of Vivitrol not only does not exclude, but also does not reduce the manifestation of symptoms associated with the abolition of alcohol intake.
Retinal occlusion
Occlusion of the retinal artery after injection of another drug containing a copolymer of lactic and glycolic acid was very rare in post-research studies, and occurred in the presence of an abnormal arteriovenous anastomosis.During the clinical and postregistration studies of Vivitrol, no cases of retinal artery obstruction were noted. Vivitrol should be used as an injection in the gluteus muscle and avoid accidental ingestion into the blood vessel.