Pharmacological properties of the drug Salbutamol
Salbutamol is a selective β2-adrenergic receptor agonist. Stimulates mainly β2-adrenergic receptors localized in the bronchi, myometrium, and blood vessels. When administered by inhalation, it acts mainly on β2-adrenergic receptors of the bronchi, with little effect on β2-adrenergic receptors of other localizations. Has a pronounced bronchodilator effect. By causing dilation of the bronchi, it relieves and prevents bronchospasm. Has virtually no effect on β1-adrenergic receptors of the heart. Prevents the release of allergy and inflammatory mediators (histamine, SRSA) from mast cells. Improves mucociliary clearance. The effect of the drug develops quickly and lasts 3–4 hours. After inhalation, approximately 10–20% of the active substance reaches the small bronchi, the rest settles in the upper respiratory tract. Plasma protein binding is 10%. Salbutamol is metabolized in the liver. It is excreted mainly in the urine unchanged and as an inactive metabolite. Most of the dose of salbutamol administered by inhalation or taken orally is eliminated within 72 hours.
Salbutamol
Salbutamol is a bronchodilator, a selective stimulator of beta-2 adrenergic receptors, which is used to relieve bronchospasm, incl. for bronchial asthma. For people suffering from bronchial asthma, it is no secret that the fastest way to stop an attack is to take a bronchodilator drug. Until the mid-20th century, adrenaline was used for this purpose, which, along with dilation of the bronchi, caused severe tachycardia and hypertension. This was due to the fact that adrenaline acted indiscriminately on both beta-1 receptors, “responsible” for the work of the heart, and beta-2 receptors, “supervising” the bronchi. Such indiscriminate action is unacceptable for many patients (primarily those suffering from cardiovascular diseases). This necessitated the creation of a group of drugs that would act primarily on beta-2 adrenergic receptors. The “flagship” of this group of drugs was Salbutamol, which was first synthesized and received the trade name “Ventolin”. Subsequently, many companies began to produce generics of Ventolin, incl. under the trade name "Salbutamol". Today this drug is the first-line drug for eliminating signs of suffocation. The inhalation method of administering beta-2-adrenergic agonists for bronchial asthma is optimal: in this way, the active component of the drug enters directly into the area of therapeutic action - the respiratory tract. The advantage of this method of administration is the speed of development of the pharmacological effect, the insignificance of the therapeutic dose, and the reduced risk of developing undesirable side reactions. With the help of Salbutamol, it is possible to successfully stop bronchial spasms, reduce resistance in the respiratory tract, and increase vital capacity.
The drug prevents the release of the mediator of allergic reactions, histamine. The frequency and strength of heart contractions are affected only to a minor extent. Doesn't reduce blood pressure. Salbutamol in injection form is quickly absorbed into the systemic circulation, while its plasma content remains at a low, barely detectable level. When taken orally, it is quickly and completely absorbed from the digestive tract. The drug undergoes metabolic transformations only in the liver; it is not metabolized in the lungs, and therefore its elimination depends on the route of administration. Half-life is 2-7 hours. Elimination from the body is carried out by the kidneys and, to a lesser extent, by the intestines. The drug is contraindicated in a number of conditions associated with pregnancy, in case of hypersensitivity of the body to the active component. If it is necessary to use Salbutamol in pregnant women, it is necessary to carefully weigh all the risks for the mother and fetus and correlate them with the expected benefits of pharmacotherapy. Increasing the dose and frequency of use of the drug is carried out under medical supervision. During the entire medication course, in patients with severe bronchial asthma, the content of potassium ions in the blood is monitored to prevent the development of hypokalemia, the risk of which increases with oxygen deprivation. When using Salbutamol together with non-selective beta-blockers, mutual neutralization of the pharmacological effects is possible. When combining the drug with theophylline, an increase in heart rate and rhythm disturbances is possible. Co-administration of Salbutamol with glucocorticosteroids increases the risk of hypokalemia.
Indications for use of the drug Salbutamol
BA (prevention and relief of attacks), chronic obstructive bronchitis, emphysema and other diseases that occur with bronchospasm. As a tocolytic agent, it is indicated for the threat of premature birth, isthmic-cervical insufficiency, a decrease in the fetal pulse depending on uterine contractions during periods of cervical dilatation and expulsion, for prophylactic purposes - during operations on the pregnant uterus (application of a circular suture for insufficiency of the internal uterine pharynx) .
Salbutamol-Pharmstandard HF 100 mcg/dose dosed aerosol for inhalation, 200 doses
Registration Certificate Holder
PHARMSTANDARD-LEKSREDSTVA (Russia)
Dosage form
Medicine - Salbutamol-Pharmstandart
Description
Aerosol for inhalation dosed
in the form of a white or almost white suspension; upon exiting the container, it is sprayed in the form of an aerosol cloud.
1 dose
salbutamol sulfate 120 mcg, which corresponds to the content of salbutamol 100 mcg
Excipients
: ethanol (absolute ethyl alcohol) - 5.905 mg, oleic acid - 0.009 mg, propellant R134a (1,1,1,2-tetrafluoroethane) - 67.966 mg.
200 doses - aluminum cylinders (1) with a dosing valve and a spray nozzle - cardboard packs.
Indications
Prevention and relief of bronchospasm in all forms of bronchial asthma. Reversible airway obstruction in chronic bronchitis and emphysema, broncho-obstructive syndrome in children.
Threatened premature birth with contractile activity of the uterus; childbirth before 37-38 weeks of pregnancy; isthmic-cervical insufficiency, a decrease in fetal heart rate depending on uterine contractions during periods of cervical dilatation and expulsion. For preventive purposes during operations on the pregnant uterus (application of a circular suture in case of insufficiency of the internal os of the uterus).
Contraindications for use
Threat of miscarriage in the first and second trimesters of pregnancy, premature placental abruption, bleeding or toxicosis in the third trimester of pregnancy; children under 2 years of age; hypersensitivity to salbutamol.
pharmachologic effect
Beta-adrenergic agonist with a predominant effect on β2-adrenergic receptors (localized, in particular, in the bronchi, myometrium, blood vessels). Prevents and relieves bronchospasm; reduces resistance in the respiratory tract, increases the vital capacity of the lungs. Prevents the release of histamine, a slow-reacting substance from mast cells and neutrophil chemotaxis factors. Compared to other drugs in this group, it has a less pronounced positive chrono- and inotropic effect on the myocardium. Causes expansion of the coronary arteries, practically does not reduce blood pressure. It has a tocolytic effect, reducing the tone and contractile activity of the myometrium.
Drug interactions
With simultaneous use of salbutamol with non-cardioselective beta-blockers, mutual suppression of therapeutic effects is possible; with theophylline - the risk of developing tachycardia and arrhythmia, in particular supraventricular extrasystole, increases.
With the simultaneous use of salbutamol and xanthine derivatives, corticosteroids or diuretics, the risk of developing hypokalemia increases.
Dosage regimen
Orally as a bronchodilator for adults and children over 12 years of age - 2-4 mg 3-4 times a day, if necessary, the dose can be increased to 8 mg 4 times a day. Children aged 6-12 years - 2 mg 3-4 times a day; children 2-6 years old - 1-2 mg 3 times a day.
When administered by inhalation, the dose depends on the dosage form used, the frequency of use depends on the indications and the clinical situation.
As a tocolytic agent, it is administered intravenously in a dose of 1-2 mg.
Side effect
From the cardiovascular system:
transient dilatation of peripheral vessels, moderate tachycardia.
From the side of the central nervous system:
headache, dizziness, nausea, vomiting.
From the side of metabolism:
hypokalemia.
Allergic reactions:
in isolated cases - angioedema, allergic reactions in the form of skin rash, urticaria, arterial hypotension, collapse.
Other:
tremor of the hands, internal trembling, tension; rarely - paradoxical bronchospasm, muscle cramps.
special instructions
Use with caution for tachyarrhythmias and other heart rhythm disorders, arterial hypertension, myocarditis, heart defects, aortic stenosis, diabetes mellitus, thyrotoxicosis, glaucoma, acute heart failure (subject to careful medical supervision).
Increasing the dose or frequency of taking salbutamol should be done under the supervision of a physician. Reducing the interval is possible only in exceptional cases and must be strictly justified.
When using salbutamol, there is a risk of developing hypokalemia, therefore, during treatment in patients with severe bronchial asthma, the level of potassium in the blood should be monitored. The risk of hypokalemia increases with hypoxia.
Use during pregnancy and breastfeeding
Restrictions during pregnancy - Contraindicated. Restrictions when breastfeeding - With caution.
Salbutamol is contraindicated in cases of threatened miscarriage in the first and second trimesters of pregnancy, premature placental abruption, bleeding or toxicosis in the third trimester of pregnancy.
If it is necessary to use salbutamol during pregnancy, the expected benefits of treatment for the mother should be weighed against the potential risk to the fetus. Currently, there is insufficient data on the safety of the use of salbutamol in early pregnancy. Salbutamol is excreted in breast milk, so if it is necessary to use it during lactation, the expected benefit of treatment for the mother and the possible risk for the child should also be assessed.
Use in children
Restrictions for children - Contraindicated.
Contraindicated in children under 2 years of age.
Use of the drug Salbutamol
Inhalation - adults and children over 4 years of age are prescribed 0.1 mg of salbutamol for inhalation to eliminate bronchial obstruction. If the attack does not stop within 5–10 minutes after the first inhalation, inhalation can be repeated. For preventive purposes, 0.1 mg of salbutamol is also recommended to be administered by inhalation 10–15 minutes before possible contact with the suspected allergen. With long-term use of salbutamol, use 1-2 inhalations (0.1 mg) 3-4 times a day with an interval of at least 3 hours. Long-term use of salbutamol for COPD or asthma is carried out only against the background of basic therapy. Do not use more than 10 doses (1 mg of salbutamol) per day. Orally, adults are usually prescribed 0.002 g 3-4 times a day. As a tocolytic agent to eliminate the threat of premature birth, as well as after operations on the pregnant uterus, it is administered intravenously in a dose of 5 mg in 400–500 ml of isotonic solution or 5% glucose solution at a rate of 15–20 drops (starting from 5 drops) per minute. The infusion rate is adjusted taking into account the intensity of uterine contractions and tolerance (heart rate and other hemodynamic indicators are monitored). Duration of administration: 6–12 hours.
Special instructions for the use of the drug Salbutamol
Use with extreme caution in case of hypersensitivity to sympathomimetics, severe heart disease (chronic ischemic heart disease, acute myocardial infarction, hypertrophic obstructive cardiomyopathy, rhythm disturbances), hyperthyroidism, unstable diabetes mellitus, pheochromocytoma. During pregnancy, it can be used only for health reasons. Since salbutamol passes into breast milk, its use during breastfeeding is possible only if the expected therapeutic effect for the mother outweighs the potential risk for the child. The use of salbutamol in high doses may worsen the reaction when driving a car or operating machinery. This effect is enhanced by simultaneous use of alcohol and tranquilizers.
