Pharmacological properties of the drug Omniscan
Nonionic paramagnetic contrast agent for magnetic resonance imaging (MRI). Paramagnetic properties determine contrast enhancement during MRI. The administration of the drug causes an increase in the signal from areas of the BBB that have dysfunction as a result of damage during the pathological process; this provides greater image information compared to non-contrast-enhanced MRI data. Optimal contrast enhancement is usually observed during the first minutes after drug administration (depending on the type of pathological process and tissue). Contrast enhancement usually persists for 45 minutes after injection. Does not penetrate the intact BBB. The drug is quickly distributed in the intracellular fluid. The volume of distribution is equivalent to the volume of intracellular fluid. The drug is not metabolized and does not bind to blood plasma proteins. The half-life is approximately 4 minutes and the elimination half-life is approximately 70 minutes. Excreted by the kidneys via glomerular filtration. In patients with impaired renal function (glomerular filtration rate ≤30 ml/min), the half-life is prolonged in proportion to the degree of decrease in filtration rate. In patients with normal renal function, 4 hours after an intravenous injection of gadodiamide, about 85% of the administered drug is excreted in the urine; after 24 hours, 95–98% is excreted. The renal and total clearance of Omniscan is almost identical and similar to other substances that are completely eliminated by glomerular filtration. After administration of 0.1 and 0.3 mmol/kg body weight, no dose-dependent changes in the pharmacokinetics of the drug were detected.
Omniscan 0.5 mmol/ml 15 ml No. 10 bottles
Content
Pharmacological action Indications Dosage regimen Side effects Use during pregnancy and lactation Use for impaired renal function Use in children Special instructions
pharmachologic effect
Contrast diagnostic paramagnetic nonionic agent. Thanks to its paramagnetic properties, it provides enhanced image contrast during magnetic resonance imaging (MRI) and facilitates the visualization of abnormal structures or formations in the body, incl. in the central nervous system. Causes an amplification of the signal in those areas where there is dysfunction of the blood-brain barrier due to its damage during the pathological process. Pharmacokinetics After intravenous administration, gadodiamide is quickly distributed in the extracellular fluid. Vd is equivalent to the volume of extracellular fluid. The half-life of distribution is approximately 4 minutes. No protein binding was detected.
Does not penetrate the intact blood-brain barrier.
The half-life is approximately 70 minutes. Almost completely excreted unchanged by the kidneys by glomerular filtration. 4 hours after intravenous injection, 85% of the active substance is determined in the urine, after 24 hours - 95-98%.
Indications
For contrast enhancement during MRI of the head, spinal canal, and whole body.
Dosage regimen
When administered intravenously to adults and children over 2 years of age weighing up to 100 kg, the single dose is 0.1 mmol/kg; for body weight more than 100 kg, a single dose is 10 mmol.
Side effect
- From the central nervous system: rarely - dizziness, headache, changes in taste and smell; in isolated cases - drowsiness.
- From the digestive system: rarely - nausea; in isolated cases - drowsiness.
- Allergic reactions: rarely - urticaria, itchy skin, sore throat.
- Other: a feeling of warmth or coldness throughout the body is possible.
- Local reactions: possible local pain, sensation of pressure at the injection site. Contraindications for use
- Renal failure, hypersensitivity to gadodiamide.
Use during pregnancy and breastfeeding
Use during pregnancy is possible only in cases of extreme necessity. During lactation, breastfeeding should be stopped at least 24 hours before administration of gadodiamide and resumed no earlier than 24 hours after its administration.
Experimental studies in rodents have shown that gadodiamide does not affect fertility and is not teratogenic.
Use for renal impairment
Contraindicated in renal failure. Should not be used in patients with impaired renal function with a glomerular filtration rate less than 30 ml/min.
Use in children
Clinical data on the use of gadodiamide in children under 2 years of age are limited.
special instructions
Should not be used in patients with impaired renal function with a glomerular filtration rate less than 30 ml/min.
Gadodiamide should be administered under conditions that allow immediate intensive care, if necessary.
Clinical data on the use of gadodiamide in children under 2 years of age are limited.
Gadodiamide distorts the results of measuring the concentration of calcium in the blood plasma, which are carried out using the colorimetric method, as well as the results of determining some electrolytes (including iron). Therefore, these studies are not recommended to be carried out within 12-24 hours after administration of gadodiamide. Drug interactions
No clinically significant interaction of gadodiamide with other drugs has been established.
Use of the drug Omniscan
For IV administration 2 hours before the procedure, the patient should stop eating. When administering the drug, the patient should be in a horizontal position. Within 30 minutes after completion of the procedure, it is necessary to ensure the possibility of providing emergency assistance, including medication, since most side effects occur during this period. Contrasting brain structures The recommended dose for children over 6 months of age is 0.1 mmol/kg (0.2 ml/kg) for body weight up to 100 kg; more than 100 kg - to ensure diagnostically adequate contrast, 20 ml of the drug is usually sufficient. The required dose must be administered intravenously at the same time. To ensure complete administration of the drug, you can rinse the IV catheter with 0.9% sodium chloride solution. In adult patients, if there is a suspicion of metastatic lesions of the brain, it is possible to administer the drug in a double or triple dose of up to 0.3 mmol/kg (0.6 ml/kg) with a body weight of up to 100 kg; more than 100 kg - to ensure diagnostically adequate contrast, 60 ml of the drug is usually sufficient. In case of ambiguous study results after contrast enhancement with Omniscan at a dose of 0.1 mmol/kg, a repeated bolus injection of the drug over the next 20 minutes at a dose of 0.2 mmol/kg can help obtain additional diagnostic information. Contrasting body tissues and internal organs The recommended dose for adult patients is 0.1 mmol/kg (0.2 ml/kg) or, if necessary, 0.6 ml/kg. For body weights over 100 kg, 20–60 ml of the drug is usually sufficient to provide diagnostically adequate contrast. The recommended dose for children over 2 years of age is 0.1 mmol/kg (0.2 ml/kg). For both adults and children, the required dose is administered intravenously at the same time. To ensure complete administration of the drug, the IV catheter should be rinsed with 0.9% sodium chloride solution. Magnetic resonance imaging Contrast -enhanced magnetic resonance imaging should begin within a few minutes of drug administration, depending on the pulse sequences used and the examination protocol. For magnetic resonance imaging with contrast enhancement by Omniscan, T1-weighted pulse sequences are optimal.
Omniscan®
In cardiac MRI, two injections are performed to study perfusion during exercise and at rest. When performing an intravenous bolus injection for cardiac MRI, it is recommended to use a suitable injector with a contrast flow rate of up to 8 ml/sec.
To ensure the full dose of contrast agent is administered, the dropper can be flushed with 0.9% sodium chloride solution.
For intravenous jet administration, once with a syringe through a catheter. Omniscan® must be drawn into the syringe immediately before use. The patient must stop eating 2 hours before the procedure.
When administering the drug, the patient should be in a horizontal position. Within 30 minutes after the end of the procedure, medical supervision of the patient is carried out, because Most adverse reactions occur during this period. In children under 1 year of age and patients with moderate kidney disease (glomerular filtration rate 30-59 ml/min/1.73 m2), the use of the drug should be assessed from a risk-benefit point of view and limited to the administration of a standard dose (0.1 mmol/kg body weight). Repeated administration of the drug should not be carried out earlier than after 7 days.
CNS contrast
For adults and children over 4 weeks.
The recommended dosage is 0.1 mmol/kg body weight (equivalent to 0.2 ml/kg body weight) for body weight up to 100 kg; more than 100 kg - 20 ml is usually sufficient to provide diagnostically adequate contrast. The required dose should be administered once intravenously.
To ensure complete administration of the drug, the intravenous catheter should be flushed with a sufficient amount of 0.9% sodium chloride solution.
For adult patients
If brain metastases are suspected, patients weighing up to 100 kg can be given a dose of 0.3 mmol/kg b.w. (equivalent to 0.6 ml/kg body weight). For body weights over 100 kg, a dose of 60 ml is usually sufficient. The dose was 0.3 mmol/kg body weight. administered as a bolus injection. If unclear images are obtained after injection at a dose of 0.1 mmol/kg body weight, a second bolus injection at a dose of 0.2 mmol/kg body weight (equivalent to 0.4 mg/kg body weight) is administered 20 minutes later.
Full body contrast
For adult patients
For patients weighing up to 100 kg, the recommended dosage is usually 0.1 mmol/kg body weight (equivalent to 0.2 ml/kg body weight) or, in some cases, 0.3 mmol/kg b.w. (equivalent to 0.6 ml/kg body weight). If the patient weighs more than 100 kg, 20 ml or 60 ml (for some cases) is usually sufficient for diagnostic contrast.
For children over 6 months
The recommended dosage is 0.1 mmol/kg b.w. (equivalent to 0.2 ml/kg body weight)
As for adults, the required dose should be administered once intravenously.
Magnetic resonance examination
Contrast-enhanced MRI should begin soon after contrast agent administration, depending on the pulse mode used and the study protocol. Optimal enhancement occurs a few minutes after injection (time determined by lesion/tissue type). Enhancement usually persists for up to 45 minutes after contrast agent administration. When using Omniscan® contrast enhancement, it is optimal to use T1-weighted pulse sequences. In the studied field strength range from 0.15 Tesla to 1.5 Tesla, the relative image contrast does not depend on the applied field strength.
Angiography
For adult patients
The recommended dosage is usually 0.1 mmol/kg (0.2 ml/kg).
In the case of stenosis of the abdominal and iliac arteries, a higher dose of up to 0.3 mmol/kg (equivalent to 0.6 ml/kg) is used, which allows additional diagnostic information to be obtained.
For optimal contrast enhancement, imaging should be performed during the first pass of contrast material, during injection, and immediately after injection, depending on the equipment used.
Coronary heart disease (CHD)
For adult patients
The recommended dosage for assessing cardiac perfusion is 0.15 mmol/kg body weight (equivalent to 0.3 ml/kg body weight), divided into 2 separate doses of 0.075 mmol/kg body weight (equivalent to 0.15 ml/kg body weight ) and administered at intervals of ≥10 minutes. The first injection is administered under conditions of pharmacological stress, the second - at rest.
The drug that causes pharmacological stress should be administered through a separate catheter. If late enhancement is assessed, a total dose of 0.15 mmol/kg body weight is recommended. The use of the drug for ischemic heart disease in children has not been studied.
Side effects of the drug Omniscan
Fever, dizziness, facial flushing, increased sweating, headache, drowsiness, loss of consciousness, tinnitus, changes in taste, myalgia, and arthralgia were rarely observed. Allergic reactions include skin itching, urticaria, sore throat; anaphylactic shock develops extremely rarely (0.01–0.10%). From the gastrointestinal tract, decreased appetite, abdominal pain, diarrhea, nausea, and vomiting are possible. Very rarely - renal dysfunction. From the blood system - asymptomatic decrease in serum iron levels (for 8-48 hours after administration of the drug).
Special instructions for the use of the drug Omniscan
The drug is not used during pregnancy, except in cases where contrast-enhanced MRI is absolutely necessary and it is not possible to replace this study with other methods. Breastfeeding should be stopped before administration of the drug and resumed no earlier than 24 hours after injection. Before using a contrast agent, it is necessary to obtain accurate information about the patient, including important laboratory and instrumental data (serum creatinine level, ECG, history of allergic reactions, pregnancy). Due to the possibility of developing anaphylactic shock during drug administration, it is necessary to create all conditions for immediate intensive care. Before the study, the patient's fluid and electrolyte balance must be restored. This especially applies to patients with multiple myeloma, diabetes mellitus, polyuria, as well as infants and young children, and elderly patients. The absence of contrast enhancement is not the only possible evidence of the absence of pathology, since some types of neoplasms or non-contrast plaques in atherosclerosis are not contrasted. The presence or absence of contrast enhancement can be used to differentiate the diagnosis. Vials are intended for one patient only. When administering other drugs, you must use a separate syringe and needle. Unused remains of the drug should be destroyed. It is not recommended to conduct a preliminary test for individual hypersensitivity to the drug using it in small doses due to the risk of developing severe hypersensitivity reactions. Omniscan changes the results of determining the concentration of calcium and iron in blood serum using some colorimetric (complexometric) methods commonly used in medical institutions. It is not recommended to use these methods for 12–24 hours after Omniscan administration. If the color of the solution changes or if large particles are present, the drug should not be used.
