Lapidary preparations: indications and effects in cardiac diseases
Digitalis is a genus of flowering plants, which are used as a medicament for disorders of cardiac activity.
The cardiotropic properties of this flower have been known for a long time. In the first half of the 18th century, it began to grow in Russia in pharmacy gardens, and since 1775, when the works of the British physician Withering were published, the preparations of digitalis took a firm place in the practice of the therapy of heart diseases.
Botanical characteristics of digitalis
Genus Digitalis is a perennial flowering plant of the Podorozhnikov family with large inflorescences of thimbus-like flowers and fragile wrinkled leaves. Blossom in the middle of summer( the end of June-July), fruits - bivalves egg-shaped with small brown seeds. In total, 36 types of foxglove are described, of which only 5 are used for medical purposes: foxglove( main source of raw materials), purple, ciliated, large-flowered and rusty.
Initially, the foxglove preparation was an extract from the leaves of the first and second year. Currently, pharmaceutical preparations of digitalis glycosides are obtained from aboveground parts of the plant, oblique before flowering.
All foxgloves are poisonous, which indicates a large number of biologically active substances and requires careful handling.
Chemical components and use of digitalis
Medicines of digitalis include its main active substances - cardiac glycosides: digitoxin, githoxin, digoxin, acetyl digoxin and many others, as well as organic acids, saponins, flavonoids.
Most active components have a secondary hydrolysis origin, that is, they are obtained by enzymatic cleavage of molecules of natural glycosides.
Digitalis preparations are used in the treatment of many cardiological diseases, mainly associated with cardiac and vascular disorders:
- Cardiac insufficiency and various organic lesions of cardiac structures( including as a preventive measure).
- Heart valve flaws, leading to decompensation. Atrial fibrillation.
- Inflammation and degeneration of the heart muscle. Paroxysmal tachycardia in pregnant women.
- Preparing for cardiac operations.
In cases of abnormalities in the conductive system of the heart( blockades) and bradycardia, the digitalis glycosides are not assigned.
How the preparation of digitalis glycoside
Isolated from the herb digitalis glycosides specifically affect the cardiac muscle. With heart failure, the effect of using digitalis will be as follows:
- a decrease in heart rate;
- increased myocardial contraction force;
- lengthening the period of relaxation of the heart( diastole).
Drugs digitalis successfully used in the treatment of circulatory failure, when the heart can not cope with the movement of blood through the vessels, which is complicated by swelling and trophic disorders. In this case, from the glycoside drugs it is expected:
- increase in cardiac output( volume of blood leaving the ventricles in one reduction);
- more effective emptying of the ventricles during systole;
- decrease in the volume of blood circulating in the vessels and, as a consequence, decrease in edema;
- normalization of heart rate with tachycardia;
- acceleration of blood flow in the vascular bed;
- increased vascular tone, which is accompanied by a slight rise in blood pressure.
The toxicity of digitalis can provoke unwanted side effects: abnormalities of the digestive tract, nervous system, changes in the heart rate. Unauthorized use of these drugs is unacceptable, the treatment scheme is selected only by the doctor, taking into account the individual characteristics of the patient.
Medicines from digitalis woolly
"Celanid" is a cardiac glycoside of quick action, it is available in the form of tablets and a solution for intravenous injections. The main indications are circulatory insufficiency, tachycardia, atrial fibrillation.
"Digoxin" is characterized by increased myocardial contractility, does not disturb coronary circulation and reduces edema due to diuretic action. It is administered intravenously and orally. It is prescribed for severe circulatory disorders and during an attack of paroxysmal tachycardia as an emergency aid.
The therapeutic effect reaches a maximum after some time, when the active substances are reached in the body of a certain concentration. There is a cumulative effect( cumulative) due to the fact that the preparations of digitalis are withdrawn rather slowly.