The drug "Dopamine" looks like a crystalline powder of a white hue with a barely perceptible smell of hydrochloric acid. It has this form in the form of hydrochloride. "Dopamine" is a substance soluble in water and alcohol. It is affected by alkalis, various oxidizing agents and iron salts. Indications and contraindications for the use of the drug "Dopamine", instructions for its use are available in our publication.
The tool is available as a concentrate for infusion solution.
Pharmacological characteristics
"Dopamine" is a neurotransmitter substance. According to its metabolic properties, dopamine is a precursor of adrenaline and norepinephrine. The drug affects the corresponding receptors, and in high concentration enhances the work of α- and β-adrenergic receptors. The work of "Dopamine" is aimed at:
- increased resistance of peripheral vessels;
- increased systolic blood pressure;
- stimulation of heart contractions;
- increased cardiac output;
- minor changes in heart rate;
- significant oxygen supply.
"Dopamine" also enhances blood flow in the vessels of the brain, heart, kidneys and intestines. Glomerular filtration and sodium excretion in the kidneys increase.
Dopamine is a fast-acting drug. 5-10 minutes after the iv infusion, the action ends. The half-life is approximately two minutes. Half of the substance interacts with a protein in the blood plasma. The drug undergoes a process of rapid metabolism in the kidneys, liver and blood plasma due to the influence of MAO and catechol-O-methyltransferase to the state of inactive metabolites and is actively produced by the kidneys. A quarter of the dose used is converted to norepinephrine in the processes of adrenergic nerves. Due to active elimination, the drug does not accumulate in the human body even after a long time of administration.
"Dopamine": application
Indications for admission:
- Various types of shock, including traumatic, cardiogenic, postoperative, hypovolemic, endotoxic.
- Acute vascular and heart failure.
- Low cardiac output.
"Dopamine" in cardiogenic shock is especially necessary, it increases the contractile function of the myocardium.
The drug is administered intravenously. 125 or 400 ml of a five percent glucose solution or sodium chloride solution are needed at 25 or 200 mg, respectively. Thus, in 1 ml of the solution, 200 or 500 μg of the substance will be obtained. If the patient cannot be injected with large volumes of liquid, a more concentrated solution can be made so that 1 ml contains 800 micrograms of Dopamine. To do this, take 200 mg per 250 ml of solutions. The injection rate reaches 1-4 μg / kg per minute for an average body weight of 70 kg (from 2 to 11 drops of a 0.05% solution or from 1.5 to 6 drops of a 0.08% solution). The therapeutic dosage is from 5 to 9 mcg / kg in 1 min. The dosage of "Dopamine" 10-15 mg / kg per minute is applicable for vasodilation, as well as arterial hypotension. The rate of administration can be increased to 18 mgk / kg per minute. The infusion takes place without interruption and is designed for a period of 2-3 hours to 1-4 days and longer. The dose per day does not exceed 800 mg. With the introduction of "Dopamine" ECG monitoring is performed. The dose and rate of administration are determined according to the level of blood pressure, heart rate, cardiac output, heart rate and urine output. If arterial hypotension did not occur, and diuresis decreased, the dose must be reduced.
Contraindications
The drug is contraindicated in the presence of problems such as:
- arrhythmia;
- pheochromocytoma;
- prostatic hypertrophy;
- angle-closure glaucoma.
Side effects
The introduction of the substance in large doses, a high level of "Dopamine" can cause side effects, including:
- tremor;
- tachycardia;
- vasospasm;
- arrhythmia;
- respiratory rhythm disturbance;
- angina and headache;
- psychomotor agitation ;
- other manifestations of adrenomimetic action.
Since elimination of "Dopamine" is active, the above manifestations disappear if you lower the dose or stop the administration of the drug. If the rhythm is broken, it is necessary to use antiarrhythmic drugs, including Verapamil, Lidocaine and others. Extravasation of the "Dopamine" solution can lead to necrosis of the subcutaneous fat and the skin itself.
special instructions
"Dopamine" during pregnancy can be prescribed only when treatment is strictly necessary for the mother, and the therapeutic effect is higher than the risk to the fetus.
A fresh solution should have a transparent consistency and no extraneous shade.
Concomitant use with other drugs
The drug can be taken in parallel with cardiac glycosides and diuretics (for example, furosemide and others). Hypovolemic shock requires the introduction of "Dopamine" together with whole blood, plasma or plasma substitutes.
You can not take "Dopamine" at the same time as "Cyclopropane", MAO inhibitors and anesthetics with halogen ("Fluorotan" and others).
Solutions of the drug must not be mixed with alkaline solutions of other drugs.
"Dopamine" is a medication that is used only as directed by a doctor. Its price depends on the dosage and the number of ampoules in the package and ranges from 80 to 300 rubles per pack (5-10 ampoules).