The medical drug Naltrexone FV is an active substance that blocks opioid receptors. This type of receptor belongs to the metabotropic type and is a semi-spiral receptor associated with g-proteins.
The active substance of the drug is a specific opiate receptor antagonist. In the process of competitive binding to all four types of receptors, the effects of opioid substances (narcotic-type analgesics and their defective substitutes), both produced in the human body (endogenous type) and received from outside (exogenous type), are prevented or eliminated. With the introduction of opioid drugs in increased dosage, there is a decrease or complete elimination of the activity of Naltrexone FV.
During therapy, the active component of the drug does not show a clinically significant pharmacological effect on the human body. The exception is a possible narrowing of the pupil.
The use of the drug in a dosage of fifty milligrams, over a twenty-four-hour interval, inhibits the pharmacological effects that are caused by intravenous injection of twenty-five milligrams of heroin. When using the drug in a hundred-milligram dosage, the period of its exposure increases to forty-eight hours. And when you take one hundred and fifty milligrams of Naltrexone FV, the duration of the effects increases to seventy-two hours.
The drug does not cause addiction or drug dependence.
After oral use, the active substance of the drug is actively absorbed in the gastrointestinal tract. This is followed by metabolic reactions in the liver, in which the formation of active metabolites (2-hydroxy-3-methoxy-6-β-naltrexone and 6-β-naltrexone) occurs. The main product of metabolism is 6-β-naltrexone, which exhibits the properties of an opiate antagonist. The maximum concentration of active substances in the patient's blood accumulates for sixty minutes after using the drug. The drug has the properties of active penetration through histiocytic barriers.
The drug is excreted by the urinary system (invariably 1% and in the form of metabolites 38%).
How does Naltrexone work?
Indications for use
The drug is prescribed in the following situations:
For combined therapy with an established diagnosis of opioid dependence (drug addiction), to maintain conditions that cause the body's resistance to the characteristic effects of opioids. It should be noted that the medication should be prescribed only when stopping an abstinent state.
For complex and supportive therapy of alcohol dependence, when using dosages similar to the treatment of heroin addiction in combination with psychotherapy.
Contraindications for the use of the drug Naltrexone FV are:
- Individual intolerance or hypersensitivity to the components of the drug.
- Conducting therapy with analgesic drugs of a narcotic nature or a positive test result for opiates in the urine.
- Lack of information about conducting a provocative test with the active substance of the drug.
- Inflammatory processes in the liver of an acute nature or insufficiency of functional activity of the liver.
In cases of impaired renal or hepatic functions, in pregnant patients and nursing mothers, in patients under the age of eighteen, the use of the drug is carried out with extreme caution and under strict medical supervision. These conditions are because currently there is not enough information about the conduct of clinical trials of the drug during pregnancy, lactation, and in persons younger than eighteen years. The effect of the drug on the health of patients in these groups is not known.
During therapy, the following negative manifestations may develop from different systems of the patient's body:
Often: there may be a feeling of nausea, vomiting, abdominal pain.
In rare cases: it may decrease or increase appetite, develop symptoms of anorexia, digestive disorders, damage to the mucous membrane of the gastrointestinal tract erosive-ulcerative type, increase gas formation. And there may also be a feeling of dryness in the oral cavity, pain in the epigastric region, aggravate the negative manifestations of hemorrhoids, increase the gas formation and increase the activity of alanine aminotransferase and aspartate aminotransferase.
Often: there may be feelings of pain in the head, anxiety, nervousness, General fatigue and weakness, sleep disorders, and nightmares.
In rare cases: may develop feelings of dizziness, drowsiness, irritability, loss of orientation, the fog of consciousness, hallucinations, ringing, and stuffy ears, burning and painful eyes and photophobia. There may also be depressing effects on the Central nervous system and visual clarity disorders.
In rare cases: there may be effects of nasal congestion, sneezing, coughing, increased production of bronchial secretion and mucus from the nasal sinuses, inflammatory processes of the mucous paranasal sinuses, breathing difficulties, bronchial obstruction, disorders of the vocal cords. It is also possible to experience nosebleeds and dyspnea.
In rare cases: there may be a pain in the chest, increased pressure in the arteries, develop the effects of tachycardia and palpitations. It is also possible to change the parameters of the electrocardiogram of a non-specific nature, and there may be manifestations of phlebitis.
In rare cases: there may be a discomfort when urinating, an increase in the frequency of urination, the development of puffiness in the facial area, and extremities. And men can also develop dysfunctions in the sexual sphere, in particular, reduce potency and delay ejaculation.
Often: rash reactions, redness of the skin may occur.
In rare cases: the patient's body temperature may rise, there may be a feeling of itching, chills, and increased sweating.
Often: painful sensations may develop in the area of muscles and joints.
In rare cases: a feeling of thirst, a decrease or increase in body weight, pain in the groin, the appearance of inflammation on the skin of the face, hair loss. It is also possible to increase the size of the lymph nodes and increase the concentration of white blood cells in the blood.
With the development of opiate withdrawal syndrome, it is possible to develop abdominal pain, spasms in the epigastrium, increased body temperature, feelings of anxiety, nervousness, General fatigue and weakness, increased irritability, digestive disorders, increased heart rate, increased nasal mucus, increased sweating, soreness in the muscles and joints, lack of appetite, the development of nausea and vomiting, a state of tremor.
When using the drug Naltrexone FV in a dosage exceeding 200 mg per day, the development of hepatotoxic manifestations is possible.
If the side effects described in the instructions occur, it is recommended to stop using the product and consult a specialist doctor.
Method of use and dosage
The drug is used orally.
Before you start using Naltrexone FV, you should consult with a specialist doctor and carefully read the instructions for use.
For the treatment of heroin addiction, therapy begins in specialized institutions that treat drug addiction.
The therapeutic course can be prescribed no earlier than seven to ten days after the last use of narcotic substances and in the case of a non - abstinent state. The period of abstinence is determined after conducting appropriate urine tests that measure the content of opiates and conducting provocative tests that involve the intravenous administration of naloxone. Tests are not allowed to be performed if patients have signs of withdrawal and the presence of opioids in urine tests. Repeated tests can be performed after some time equal to one day.
During the therapeutic course, the patient must be under the constant supervision of a specialist doctor. An important role in therapy is the presence of a positive psychological attitude to treatment for addiction.
For maintenance treatment, a drug is prescribed in a dosage of 50 mg at an interval of twenty-four hours (this does inhibit the pharmacological effects that are caused by intravenous injection of twenty-five milligrams of heroin).
Other therapy regimens may be used:
- Using the drug Naltrexone FV in a dosage of 50 mg for the first five days of the week and taking 100 mg on Saturday.
- Use of the drug in a dosage of 100 mg once a day or 150 mg once every three days.
- Use of the drug in a dosage of 100 mg on the first and third days of the week, and 150 mg on the fifth day of the week.
The minimum duration of the therapeutic course is three months.
The standard duration of therapy is six months.
For the treatment of alcohol dependence, the medicine is used daily in a dosage of 50 mg. The duration of the minimum therapeutic course is three months.
Currently, there is no reliable information about the possible overdose of the drug and the development of negative manifestations in this case. However, it can be assumed that the symptoms of overdose may be the above-described side effects.
If an overdose is suspected, it is necessary to conduct symptomatic therapy and consult a specialist doctor.
Features of use
During the therapeutic course, the patient must have a card with the prescription of the drug Naltrexone FV, so that in emergencies, emergency medical workers were informed about the use of this drug.
If there is a need to cancel the blocking of opioid receptors, in particular during anesthesia and analgesia, increased dosages of analgesic substances of the opioid type are used, with short exposure time.
Before starting therapy, it is necessary to make sure that the patient does not have liver failure. During the therapeutic course, the activity of liver enzymes should be monitored.
The use of the drug should be interrupted at least two days before the intended operations if they require the use of opioid-type analgesics.
If it is necessary to carry out emergency analgesia with opiate substances in an increased amount, their administration should be carried out with great caution, since the effects that depress the functions of the respiratory system may have an increased duration.
To prevent the development of acute withdrawal conditions, it is necessary to stop taking opiates seven to ten days before starting therapy with a medical drug. Before starting therapy, tests are required to confirm the absence of opioids in the urine, as well as a provocative sample. If you do not follow the instructions described above, you may develop withdrawal syndrome for five minutes after use and last for two days.
If there are negative symptoms, manifested in the development of pain in the abdominal area, changes in the color of the urine, the appearance of a yellow tint on the sclera, you should stop therapy and consult a specialist doctor. Lack of appetite and a sharp decrease in the patient's body weight requires the drug to be discontinued.
Exposure to the drug is not effective for treating addiction to cocaine and non-opioid medications.
Interaction with other medications
Treatment with certain opioid drugs (in particular, cough medications, anti-inflammatory substances, analgesics) against the background of Naltrexone FV therapy may be ineffective, due to the specific properties of the substance described. It is recommended to replace these medications with substances that do not contain opiates in their composition.
Simultaneous therapy with hepatoxic agents mutually increases the possibility of liver disorders.
Combined use with thioridazine may cause lethargy or increased drowsiness.
The use of a drug can accelerate the occurrence of negative effects of a withdrawal syndrome in drug addiction.
Other cases of negative interaction with medications are not known.
Use during pregnancy and breast-feedin
It is not recommended to conduct drug therapy in pregnant women and nursing mothers since the effect of the drug on this group of patients is not currently studied.
Interaction with alcohol
It is forbidden to drink alcoholic beverages during the treatment period.
According to the instructions, the storage of the product must be carried out at a temperature no higher than twenty-five degrees of heat. If the storage rules are observed, the shelf life of the drug is thirty-six months.