Vasodilator - what is it? Description of the pharmacological group

Vasodilation is the process of relaxing the muscle layer of the vascular wall. A drug that has a similar mechanism of action and is used in the treatment of heart failure and hypertension is called the corresponding term - vasodilator. What is it and what means relate to vasodilators, we will consider further.

General information

A decrease in cardiac output, which develops in heart failure, activates the adrenergic nervous and renin-angiotensin systems, resulting in the release of angiotensin II and norepinephrine. Active substances bind to receptors, which leads to vasoconstriction.

The first stage of heart failure requires a similar mechanism, since this allows you to maintain the necessary level of blood pressure. However, prolonged narrowing of the veins leads to the development of congestive processes in the lungs and a decrease in cardiac output.

Vasodilators are drugs (a list of names can be found in the specialized medical and pharmacological literature, in addition, below we will list the most popular drugs in this group) used for vasodilatation. The result is the development of an antihypertensive effect. Another important indication for prescribing this kind of medication is heart cough. How will vasodilators help with this condition? Drugs for heart cough are used to expand the coronary vessels.

Drug classification

Depending on which areas of the vascular bed are affected by active substances, three groups of vasodilators are distinguished:

1. Arterial:
   • "Hydralazine";
   • calcium antagonists.
2. Venous:
   • nitrates;
   • sydnimines.
3. Mixed Type:
   • angiotensin II receptor blockers ;
   • ACE inhibitors;
   • alpha1-blockers;
   • sodium nitroprusside.

Venous vasodilator drugs

Venous vasodilator - what is it? This is a drug that causes a decrease in the tone of the venous vascular wall. Venules respond to lower concentrations of active substances than arteries. In such cases, nitrates are used, which help to relax large veins, increase the volume of the bloodstream, reduce the load on the heart, and reduce the need for myocardium in oxygen.

Venous vasodilators - drugs (names, doses are described in the table), which are considered the safest of all antianginal drugs. Side effects are rare and short-lived.

Arterial vasodilator drugs

Arterial vasodilator - what is it? This is a medication, the active substance of which helps to relax the muscle tissue of the arterial wall.

For example, "Hydralazine" is a drug that increases heart rate, enhances blood flow in the kidneys and brain, which occurs as a reflex response to the removal of vascular spasm. It is used for various forms of hypertension, hypertensive crisis in combination with other agents.

Side effects of hydralazine:

• cephalgia;
• facial redness;
• the appearance of edema;
• worsening manifestations of angina pectoris;
• a condition similar to systemic lupus erythematosus.

"Diazoxide" - a vasodilator that is used exclusively for the relief of hypertensive crisis. It is administered intravenously, lowers blood pressure in 2-3 minutes. In addition, the drug causes a strong relaxation of the uterus and water retention in the body.

Calcium antagonists - a group of arterial vasodilators, including the following:

1. "Nifedipine" - eliminates spasm of the coronary vessels, reduces blood pressure, reduces the work of the heart muscle.
2. "Verapamil" - reduces myocardial contractility, restores heart rate and blood pressure.

Mixed Type Drugs

Mixed vasodilator - what is it? This is a drug whose active substance relieves spasm of arteries and veins. One of the most effective is sodium nitroprusside. According to the mechanism of action, it is similar to nitrates. Intravenous administration of the drug causes a quick and strong effect, but it is short-lived.

A vasodilator is used in case of acute and chronic heart failure, a hypertensive state against a background of myocardial infarction, encephalopathy against a background of hypertensive manifestations. The introduction of sodium nitroprusside can cause dizziness, the appearance of a headache, loss of consciousness, nausea, tachycardia.

ACE inhibitors - a group of drugs that block the formation of angiotensin-converting enzyme, as a result of which angiotensin II is not produced. In parallel, there is an increase in the effect of diuretics. The classification of ACE inhibitors is based on their chemical structure:

1. Containing sulfhydryl group:
   • Captopril.
   • Zephenopril.
   • Benazepril.
2. Containing a carboxyl group:
   • Lisinopril.
   • Enalapril.
   • Spirapril.
3. Containing a phosphinyl group:
   • Fosinopril.

The drugs have advantages for asymptomatic left ventricular dysfunction, carotid arteriosclerosis, metabolic syndrome, microalbuminuria, atrial fibrillation, a history of myocardial infarction, and non-diabetes nephropathy.

Children's vasodilators

Vasodilator preparations for children are used exclusively for severe pathologies. As a rule, myotropic drugs ("Dibazol", "Papaverine") and ganglioblockers ("Benzohexonium") are used.

Children receive vasodilator drugs with neurological treatment. The funds are aimed at improving cerebral circulation, are used in conditions of "white" hyperthermia and hydrocephalus.

Any of the medicines is selected individually, it depends on the condition of the patient, the severity of the disorders, the form and course of the disease. Self-medication is strongly discouraged.