Magnilek

Magnilek is a gadopentetic acid drug used in magnetic resonance imaging (MRI).

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Indications Magnilek

Magnilek solution is used in magnetic resonance therapy (MRI) of the brain and spinal cord:

• For the purpose of detection and differential diagnosis of meningiomas, neuromas (including the auditory nerve), invasive tumors (e.g. gliomas), metastases.
• To detect small tumors and tumors that are difficult to visualize.
• In differential diagnostics of the following types of tumors: hemangioblastomas, ependymomas, small pituitary adenomas.
• To determine the intracranial spread of primary (non-brain) tumors.
• Diagnosis of tumor recurrence after surgery or radiation therapy.

MagniLek solution is used in spinal magnetic resonance imaging (MRI) for differential diagnosis and assessment of the spread of intramedullary and extramedullary tumors.

In magnetic resonance imaging (MRI) of the whole body, the drug is used:

• When examining the facial part of the skull, the neck area, the chest and abdominal cavity, the mammary glands, the pelvic organs, the musculoskeletal system, the vessels of the whole body (to assess the blood supply in normal tissues and tissues with pathological changes, when detecting tumor processes, inflammation, vascular damage).
• In differential diagnostics of tumors and scar tissue.
• Diagnosis of recurrent intervertebral disc herniation after surgery.
• With simultaneous semi-quantitative assessment of renal function with zonal anatomical diagnostics.

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Release form

The medicine is available in the form of a transparent, uncolored solution or a pale yellow solution.

Compound:

• The active component of the solution is gadopentetic acid.
• One ml of solution contains 469.01 mg of gadopentetic acid as dimeglumine salt.
• Excipient: water for injection.

The form of release of the drug Magnilek is as follows:

1. Injection solution 469.01 mg/ml, 10 ml bottle, No. 1.
2. Injection solution 469.01 mg/ml, 20 ml bottle, No. 1.
   

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Pharmacodynamics

The pharmacodynamics of the drug Magnilek are as follows:

• Gadopentetate is a compound of gadolinium and pentetic acid, which has seven unpaired electrons, which cause its paramagnetic properties.
• Gadopentetic acid dimiglumine salt is a stable chelate complex that has increased hydrophilicity and strong paramagnetic properties.
• The chelate complex is not toxic. The organic component of the complex is not absorbed by the body, and the metal does not dissociate.
• After intravenous administration, the dimeglumine salt of gadopentetic acid dissociates and forms meglumine and gadopetetate ions.
• The hydrophilic chelate compound is distributed exclusively in the extracellular fluid and does not penetrate the intact blood-brain barrier. Therefore, the compound is not able to accumulate in brain cells with normal functioning or in cells with a difference from normal functioning, but having an intact blood-brain barrier.
• Violation of the blood-brain barrier or tissue vascularization stimulates the accumulation of dimeglumine salt of gadopentetic acid in the following tissues: in neoplasms, in abscesses, in the subacute period of myocardial infarction.

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Pharmacokinetics

The pharmacokinetics of Magnilek are as follows:

• In healthy patients, the pharmacokinetic profile of the administered drug is an open biphasic model with a mean distribution half-life of approximately 0.2 hours and a mean T 1/2 of approximately one and a half hours.
• About eighty percent of the drug dose is excreted from the body in the urine within six hours after administration; about 93 percent of the solution within 24 hours; less than 0.1 percent is excreted in the feces within five days.
• Gadopentetic acid passes into breast milk in small amounts (about 0.04 percent of the total amount of the drug administered).

Association, transformation and degradation of gadopentetic acid were not identified.

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Dosing and administration

The method of application of Magnilek and the doses in which it is prescribed are as follows:

• The patient should refrain from eating for two hours before the administration of the drug.
• During the injection and for at least half an hour after it, the patient must lie on his back.
• When performing MRI of the whole body and cranial, spinal magnetic resonance imaging, the drug is prescribed to adult patients at a dosage of 0.2 ml per kilogram of body weight.
• For children over two years of age, the medicine is prescribed in a dosage of 0.2 ml per kilogram of body weight.
• The medicine is used only in a hospital setting when the procedure is performed and monitored by a specialist doctor. Before the procedure, the patient undergoes a standard examination to determine whether he has pacemakers, ferromagnetic implants, and other preventive procedures.
• The solution is administered intravenously only, preferably into large veins. The rate of administration of Magnilek is 10 ml per minute. Instead of the intravenous method, a bolus injection can be used, which is administered at a rate of 15 ml per second.
• The medicine is drawn into the syringe only before injection. The solution cannot be used if it has changed color or lost transparency with the appearance of impurities. The part of the medicine that was not used during injection is subject to disposal.
• The maximum total dose of the medicine is 20 ml.
• After the Magnilek injection is completed, 5 ml of physiological solution is administered intravenously. This measure ensures the complete administration of the required amount of medicine.
• The examination begins immediately after the solution is administered and ends no more than one hour later. Such timeframes are due to the fact that in MRI of the brain, the optimal degree of contrast is recorded 27 minutes after the drug is administered, and in MRI of the spinal cord - 10-30 minutes.

• Pulse sequences with T-weighted images are considered to be the highest quality for contrast studies.
• If the tomography does not reveal any damage to the brain or spinal cord, but there are suspicions (due to the general clinical picture), then the diagnostic level of the examination is increased. This is done by introducing the solution for 30 minutes with a repeated injection of the drug in a dose equal to the previous one. Sometimes, the repeated dose for adult patients can be increased to 0.4 ml per one kg of body weight.

• Tumor recurrence and exclusion of metastases in adults are studied by administering a dose of Magnilek in the amount of 0.6 ml per kg of body weight.
• It happens that dimeglumine gadopentetate can help to lower the seizure threshold in patients prone to it. Therefore, during the procedure, such patients should be under constant supervision, and if necessary, they are given anticonvulsants.
• Patients with bronchial asthma, allergic reactions and hypersensitivity to contrast agents are prescribed preliminary administration of antihistamines and/or glucocorticoids before using the drug.
• Patients who have a known sensitivity to the components of the drug may experience severe allergic reactions, including anaphylactic shock. Therefore, it is recommended to carefully monitor the patient during the procedure and always have medications on hand that can relieve the symptoms of hypersensitivity.

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Use Magnilek during pregnancy

The use of Magnilek during pregnancy is not recommended. Because there is currently no reliable data on how gadopentetic acid affects fetal development. It is also unknown how magnetic and electric fields affect fetal development. Therefore, Magnilek and the MRI method are not recommended for use during pregnancy.

During lactation, it is recommended to use the drug and the MRI method only for vital indications. Since gadopentetic acid is excreted in breast milk in small doses. Therefore, when taking Magnilek, it is necessary to resolve the issue of interrupting breastfeeding. The shortest period of pause in breastfeeding should be at least 24 hours from the moment of administration of the drug.

Contraindications

Contraindications for the use of Magnilek are:

• Hypersensitivity to the components of Magnilek.
• Severe renal failure (with creatinine clearance less than 20 ml per minute).
• Sickle cell anemia.
• Children under two years of age (since there is no experience of using the medicine for children of this age).
• Pregnancy.

The drug should be used with special caution in patients:

• With various liver diseases and/or manifestations of hemolysis.
• With various renal dysfunctions. In patients with kidney disease, the benefits of using the drug should be carefully weighed against the risk of side effects. Since the use of Magnilek for MRI can cause acute renal failure or deterioration of renal function.
• With various allergic diseases and bronchial asthma.

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Side effects Magnilek

Side effects of Magnilek for the patient are associated with the action of gadopentetic acid during magnetic resonance imaging. They are transient in nature with mild or moderate severity. Prolonged side effects of the body were recorded in isolated cases.

The list of side effects from the administration of the drug is as follows:

• From the cardiovascular system, the following were noted: arterial hypotension, hot flashes, vasodilation, pallor of the skin, non-specific changes in the ECG, phlebitis, and chest pain.
• Attacks of angina pectoris, arrhythmia, and tachycardia may also occur.
• From the nervous system, possible manifestations include headache, drowsiness, dizziness, increased excitability, speech disorders, confusion, hypersthenia, paresthesia, tinnitus, tremors, convulsions, and visual impairment (appearance of visual field defects).
• From the gastrointestinal tract, the following may occur: nausea and vomiting, pain and spasms of the stomach and intestines, diarrhea, thirst, hypersalivation, taste disturbances (especially after a bolus injection), pain and paresthesia of the soft tissues of the oral cavity, toothache.
• From the respiratory system, the following may occur: dry mouth and sore throat, rhinorrhea, pain in the throat and larynx, sneezing and wheezing, laryngospasm, cough, shortness of breath or apnea, swelling of the larynx and pharynx, bronchospasm, pulmonary edema, cyanosis.

• From the musculoskeletal system, reactions were observed in the form of pain in the back and limbs, arthralgia.
• From the skin system and mucous membranes, possible manifestations include rash and skin itching, urticaria, sweating, and angioedema.
• The following allergic reactions were observed: in isolated cases, anaphylactic or anaphylactoid reactions of the body (including the appearance of anaphylactic shock), hyperthermia, hyperhidrosis, and fluctuations in body temperature may occur.
• Local reactions of the following nature may occur: a feeling of cold or burning, pain, or swelling may occur at the injection site.
• Changes in laboratory parameters – an increase in the content of iron and total bilirubin of a reversible nature in the blood plasma, as well as an increase in the level of liver enzymes are noted.
• Other reactions include general weakness of the body, toothache, increased fatigue, changes in taste sensations (which may quickly disappear).

Special comments on side effects:

• If MagniLek is prescribed to patients with known hypersensitivity to the components of the drug, the risk/benefit ratio of the applied examination procedure should be carefully weighed. Since the use of MagniLek may cause anaphylactic or hypersensitivity reactions. Other idiosyncratic reactions may occur, such as symptoms from the cardiovascular, respiratory and skin systems up to a severe degree of reaction, including shock. Most symptoms appear within half an hour from the moment of drug administration, although sometimes delayed manifestations are observed.
• Patients with cardiovascular disease may experience symptoms of serious and even fatal consequences of severe hypersensitivity to the drug.
• Patients who suffer from bronchial asthma or allergies, hypersensitivity to contrast media, are at high risk of developing symptoms of hypersensitivity to the drug Magnilek.

The effect of Magnilek on the reaction speed and control of vehicles, robots and other mechanisms is as follows:

• Since the introduction of Magnilek solution may provoke individual psychosomatic reactions, patients who have undergone the study must temporarily (at least six hours) refrain from driving vehicles or exercise caution when driving vehicles.
• You should not engage in processes that require increased concentration, attention and speed of psychomotor reactions for at least six hours after the administration of Magnilek.

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Overdose

• Overdose of Magnilek increases the above-mentioned side effects.
• The hypersmolarity of the drug in case of overdose provokes the appearance of osmotic diuresis, increased pressure, the occurrence of hypervolemia and dehydration.
• In case of overdose, symptomatic treatment is used. Since special antidotes to the drug have not been developed. Magnilek can be removed from the patient's body by hemodialysis.

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Interactions with other drugs

The interactions of Magnilek solution with other drugs are as follows:

• Patients who use beta-blockers, for example, in bronchial asthma, may experience hypersensitivity reactions to the drug. In this case, tolerance to standard therapy of hypersensitivity reactions with beta-antagonists may be recorded.
• To date, no other reactions with other drugs have been identified.
• When interacting with diagnostic tests to determine the amount of iron in blood plasma using bathophenanthroline, the quantitative indicator may be reduced within one day.

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Storage conditions

Storage conditions for Magnilek are as follows:

1. The solution is stored at a temperature of up to 25 degrees Celsius in places protected from light and secondary X-ray radiation.
2. The drug must not be frozen.
3. The solution should be stored out of the reach of children.

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Shelf life

The shelf life of Magnilek is three years from the date of manufacture.

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