Ticket 26

1. Types of drug therapy. The dependence of the action of pharmacological agents on the initial state of the organism (the influence of age, sex, genetic factors, circadian rhythms and pathological background).

• Etiotropic (causal) therapy - elimination of the cause of the disease: the use of antimicrobial, antiviral and antiparasitic agents for infectious diseases, antidotes for poisoning. • Pathogenetic therapy - the effect on the pathogenetic mechanisms of diseases: the appointment of antihypertensive drugs for arterial hypertension, cardiac glycosides for heart failure, anti-inflammatory drugs for rheumatic diseases, psychotropic drugs for the treatment of mental disorders. • Symptomatic therapy - elimination or reduction of individual manifestations of the disease: the use of painkillers and antipyretic drugs. • Substitution therapy - replenishment of an insufficient amount of natural metabolites of the body: the use of vitamin, hormonal, enzyme agents, salts of iodine, fluorine, iron, calcium. For preventive purposes, antiseptics, disinfectants, antiviral, vitamin agents are prescribed. • Gender - Clinical studies indicate certain gender differences in drug metabolism and sensitivity to certain pharmacological effects. So, due to the fact that male sex hormones stimulate the synthesis of microsomal liver enzymes, the elimination of certain medicinal substances (paracetamol, verapamil, benzodiazepines, propranolol) occurs faster in men. The existing sex differences in ethanol metabolism are associated with the high activity of alcohol dehydrogenase in men. The arrhythmogenic effect of antiarrhythmic drugs (ventricular arrhythmias of the "pirouette" type) more often occurs in women, the analgesic effect of morphine occurs in women in lower doses than in men. Funds,

•Age. Age-related changes in drug action are especially evident in newborns and patients over 60 years of age.

Newborns are more sensitive to drugs. This is mainly due to the imperfection of the metabolism of medicinal substances (due to the lack of enzymes), reduced renal function, increased permeability of the blood-brain barrier, underdevelopment of the endocrine, nervous and other systems of the body.

In old and senile age, pharamacokinetic processes are slow. The change in the rate of absorption is mainly associated with a decrease in the acidity of gastric juice, a decrease in blood flow in the intestine, inhibition of active absorption systems, etc. A decrease in the metabolism of medicinal substances with age is associated with a decrease in the activity of liver enzymes and a decrease in hepatic blood flow. Decreased renal function leads to a slower elimination of drugs. • Genetic factors. There are significant differences in the individual sensitivity of people to drugs, determined by genetic factors. The section of pharmacology Pharmacogenetics studies the role of genetic factors in changing the action of drugs. Very often, individual differences in the action of drugs are due to differences in their metabolism. This happens due to a change in the activity of enzymes that metabolize drugs, which is often associated with a mutation of genes that control the synthesis of these enzymes. Violation of the structure and function of the enzyme is called enzymopathy (fermentopathy). With enzymopathies, the activity of the enzyme can be increased (the metabolism of drugs is accelerated and their action is weakened) or decreased (the metabolism slows down, which can lead to an increase in the action of the drug and the appearance of toxic effects). With a genetic deficiency of some enzymes, atypical reactions to substances (idiosyncrasy) may occur. With enzymopathies, the activity of the enzyme can be increased (the metabolism of drugs is accelerated and their action is weakened) or decreased (the metabolism slows down, which can lead to an increase in the action of the drug and the appearance of toxic effects). With a genetic deficiency of some enzymes, atypical reactions to substances (idiosyncrasy) may occur. With enzymopathies, the activity of the enzyme can be increased (the metabolism of drugs is accelerated and their action is weakened) or decreased (the metabolism slows down, which can lead to an increase in the action of the drug and the appearance of toxic effects). With a genetic deficiency of some enzymes, atypical reactions to substances (idiosyncrasy) may occur.

• Pathological background - various pathological conditions can cause changes in the pharmacokinetics and pharmacodynamics of drugs in diseases of the gastrointestinal tract, there may be a decrease in the rate and degree of absorption of drugs. Some diseases of the lungs and cardiovascular system lead to significant changes in hemodynamics, which affects the distribution of medicinal substances. In case of impaired renal function, the effect of substances excreted by the kidneys in an unchanged form is lengthened. In the focus of inflammation, the effect of local anesthetics is sharply weakened.