3. Preparations of water-soluble vitamins. Classification. Mechanism of action. Indications. Side effects. Contraindications Comparative evaluation of drugs.

Classification:

B1- Thiamine- Thiamine bromide, Thiamine chloride, phosphotiamine, benzothiamine

B2 - Riboflavin - Riboflavin mononucleotide, Riboflavin

B3 (PP) - Nicotinic acid - Nicotinic acid, Nicotinamide

B5-to-that Pantothenic - Calcium pantothenate

B6-Pyridoxine-Pyridoxine hydrochloride

B12-Cyanocobalamin

All-to-that folic

C-to-that Ascorbic

Vit C Mechanism: participates in the OM system, in the transport of hydrogen, in the synthesis of hyaluronic acid, collagen, hormones of the adrenal cortex, in erythropoiesis, increases the antitoxic, protein and glycogen-forming function of the liver. Used for infections, radiation sickness, trauma, anemia, hemorrhagic diathesis. side effects: With prolonged use and administration of large doses, it inhibits the insular apparatus of the pancreas and, indirectly, the kidneys, which leads to an increase in blood pressure.

Vit B1 - absorbed from the intestine, phosphorylated, and converted into thiamine pyrophosphate-coenzyme decarboxylases, i.e. decarboxylation of pyruvic acid, a-ketoglutaric acid, as well as transketolase, which is involved in the pentose phosphate pathway of glucose breakdown. Avitaminosis is a beriberi disease. It is used for diseases of the nervous system, ulcer and duodenal ulcer, hypo and anacid gastritis, myocardial dystrophy, coronary insufficiency, arrhythmias, paresis. Side effects are sometimes allergies.

Vit B6 - phosphorylated in the body, → coenzyme pyridoxal phosphate. Participates in decarboxylation, deamination, amino acid transamination, tryptophan metabolism. Avitaminosis - dermatitis, growth disorders, convulsions, anemia. Applied for violations of protein metabolism, erythropoiesis, atherosclerosis, paresis, paralysis, trauma, with toxicosis of pregnant women. Side effects - well tolerated, sometimes allergies

Vit PP - is a part of the coenzymes NAD and NADP, participates in tissue respiration, in detoxification, with dehydrogenesis in oxidative processes. It has a pronounced, but short-term vasodilating effect. Avitaminosis - pellagra. It is used for diseases of the CVS, liver, gastritis with low acidity, atherosclerosis, peripheral vascular spasms, and poisoning. Side effects - with long-term use in large doses, fatty degeneration of the liver.

Vit B12 - Mechanism: turns into a co-factor, participates in the transfer of mobile methyl groups (transmethylation process) and hydrogen. Thanks to these processes, the influence on the exchange of proteins and nucleic acids is carried out. Hypovitaminosis: diseases of the small intestine, congenital or acquired deficiency. Used for anemia, radiation sickness, liver disease, after surgery and infections. Side effects: well tolerated, sometimes causes an increase in blood clotting.

Folic acid - in the liver it is converted into the active coenzyme form 5.6.7.8 tetrahydrofolic acid, which attaches and transfers one-carbon groups, THPK is involved in the synthesis of pyrimidines, purines, the metabolism of nucleic acids and proteins. Used for macrocytic anemia, for sprue, radiation sickness, in newborns.

4. Antihelminthic agents. Classification. Mechanism of action. Indications for use. Side effects. Contraindications Comparative evaluation of drugs.

Anthelminthic agents disrupt the function of the neuromuscular system of helminths, exhibiting anticholinesterase (emetine), cholinomimetic (ditrazine, combantrine) or anticholinergic (piperazine) action. Many drugs (levamisole and others) disrupt various types of metabolism in helminths

The effectiveness of antihelminthic agents for various helminthiasis is not the same and is primarily determined by the biological species of parasitic worms and their localization in the body. On the basis of ideas about the direction of action of drugs on various classes of helminths, a classification of antihelminthic agents is constructed. In accordance with this, funds are allocated that are used mainly for the treatment of nematodes, cestedoses and trematodes.

Anthelminthic agents used mainly for nematodes

Anthelminthic drugs used mainly for cestodosis

Broad-spectrum anti-herbal remedies

One of the most effective remedies for ascariasis is levamisole (decaris). A single injection of the drug leads to deworming in 90 - 100% of patients, regardless of the degree of their infection. Unlike santonin, the drug acts on ascaris of all age groups. Levamisole is less effective in ankylostomiasis and strongyloidiasis.

The mechanism of the anthelmintic action of levamisole is based on the specific inhibition of the enzyme succinate dehydrogenase, as a result of which the fumarate reduction reaction, which is most important for nematodes, is blocked. It should be borne in mind that levamisole does not affect succinate dehydrogenase in mammals and only inhibits the helminth enzyme.

The main indication for the use of the drug is ascariasis. Treatment with levamisole (unlike treatment with many anthelmintic drugs) does not require preliminary preparation of the patient - a special diet, the use of laxatives, etc. It is used once before bedtime (for adults at a dose of 150 mg). The drug is well tolerated.

In the treatment of cestodoses, the most common remedy is male fern extract, which is highly toxic and requires careful special preparation of the patient. The main active principles of the male fern extract - philicic acid, aspidin and desaspidin - cause paralysis of the neuromuscular apparatus of flatworms.

Treatment is carried out according to a specific scheme, including diet and laxatives. The dose of the extract for adults is up to 8 g. Often there are numerous side effects in the form of nausea, vomiting, abdominal pain, palpitations. Convulsions, collapse, heart failure are possible. These side and toxic effects, as well as certain contraindications, limit the use of male fern preparations.

In modern medical practice, for the treatment of cestodosis, fenasal is mainly used, which is highly effective in theriarynchiasis, diphyllobothriasis and hymenolepiasis. Fenasal paralyzes tapeworms. In addition, it causes the destruction of the integumentary tissues of helminths and reduces their resistance to the action of proteolytic enzymes of the gastrointestinal tract, contributing to the digestion of cestodes (in this regard, phenasal is not recommended for use in teniasis due to the risk of developing cystcercosis).

Treatment with fenasal does not require special preparation of patients. It is usually taken at night after a light dinner at a dose of 3 g (for adults); with hymenolepiasis, a course treatment is carried out.

The drug is well tolerated. The high efficiency of phenasal in cestodosis, the absence of contraindications and pronounced side effects ensures its widespread use in medical practice, not only in adults, but also in children.

Ticket 41.

1. Principles of drug discovery. Ways of synthesis of pharmacological substances. Obtaining preparations from plant and animal raw materials.

The creation of drugs has developed in the following areas:

1) chemical synthesis of drugs;

2) receiving drugs from raw drugs and isolating the individual in-in (alive, growing, miner of origin);

3) isolation-e-in - products of life-giving fungi (penicillin) and microbes (interferon, interleukins, enzymes), biotechnology (use in the industry of biosystems and processes).

Chemical synthesis of drugs is carried out in 2 directions: directed synthesis and empirical path.

Directed synthesis:

Reproduction of biogenic substances - this is how adrenaline is synthesized;

creation of antimetabolites - by changing the structure of the molecule of the island, you can get its antagonist;

Modification of molecules of compounds with known biological activity

the study of the structure of the substrate with which the drug interacts - X-ray structural analysis, nuclear magnetic resonance allows you to establish a 3-dimensional structure of the island in the solution;

a combination of 2 connections with the necessary saints - genetic engineering;

synthesis based on the study of chemical transformation in org-me (prodrugs; creation of drugs that change the activity of enzymes).

The empirical path is random finds, "screening" is a laborious and ineffective path.

Many medicines (galenic, novogalene, alkaloids, glycosides) were obtained from medicinal raw materials. Biotechnology - biosynthesis of antibiotics (penicillin), the development of hybridoma technology (cell engineering), the method of recombinant DNA (genetic engineering). The industry uses biosystems and processes.

2. The history of the discovery of non-inhalation anesthesia (NI Pirogov, NP Kravkov, SP Fedorov). Classification of drugs for anesthesia. Requirements for non-inhalation anesthetic drugs. Advantages and disadvantages of non-inhalation anesthesia versus inhalation. Comparative characteristics of non-inhalation anesthetic drugs.

1846 - the discovery of anesthesia. Morton (1819-69) was an American dentist who first introduced ether anesthesia into a surgeon's practice. Pirogov (1810-81) - Russian surgeon and anatomist, the main field of military surgery. For the first time he performed an operation under anesthesia on the battlefield (1847).

Classification of drugs for anesthesia.

Inhalation : volatile liquids: ether, fluorothane, sevoflurane, isoflurane, methoxyflurane

Gaseous substances: nitrous oxide, cyclopropane, xenon.

Non-navigational : derivatives of barbituric and thiobarbituric acids: thiopental sodium, thiobutal, hexenal

Steroids: Predion.

GHB salts: sodium oxybutyrate.

Others: propofol, propanidide, ketamine.

Anesthesia is a condition characterized by the shutdown of consciousness, suppression of sensitivity, reflex reactions, and decreased tone of skeletal muscles.

The actions of anesthetic drugs are associated with the fact that they inhibit the interneuronal transmission of excitation in the central nervous system. Dysfunction of the membrane. One of the manifestations of the interaction of drugs for anesthesia with the postsynaptic neuronal membrane is a change in the permeability for ion channels (for example, for K ions), which disrupts the process of depolarization, and, consequently, interneuronal impulse transmission.

Receptor component of the action of drugs for anesthesia. All inhalation (volatile) and non-inhalation drugs (except for ketamine) in narcotic concentrations interact with GABA receptors, potentiating their action. Nitrous oxide does not affect gamk. Ketamine is an NMDA receptor antagonist. These receptors are blocked by xenon.

Ftorotane became widespread. It is characterized by high drug activity, a short stage of arousal. anesthesia is easily controlled, after the patient stops inhaling fluorothane, awakening will occur in 3-5 minutes. In terms of fire, it is safe. Has no irritating effect on the mucous membrane of the respiratory tract (unlike ether)

Respiratory side effects of fluorothane: moderately inhibits the respiratory center.

CCC: weakens myocardial contractility, reduces stroke volume, lowers blood pressure. The mechanism of hypotension is associated with inhibition of the vasomotor center and impaired transmission of vasoconstrictor impulses in the ganglia and the endings of sympathetic nerves., Cardiac arrhythmias are possible.

Kidneys: fluorothane reduces renal blood flow, SKF, diuresis, respectively.

Liver: with a healthy liver does not cause significant changes, is contraindicated in persons with liver disease.

Ether. It has a pronounced narcotic activity, sufficient arcotic breadth, relatively low toxicity. Less manageable. Irritates mucous membranes, causes a pronounced stage of arousal, explosive. Side effects: profuse secretion of the salivary and bronchial glands (the result of irritation of the mucous membranes), aspiration with vomit, which interferes with airway patency, bradycardia and even cardiac arrest due to reflex excitement of the vagus nerve. Ether is administered only against the background of premixing. Ether promotes the release of catecholamines from the adrenal medulla. This can lead to an increase in glycogenolysis, hyperglycemia (therefore, contraindicated in diabetes mellitus)

On the CVS: increased stroke and minute volume of the heart, increased heart rate, moderate narrowing of the peripheral vasculature.

Liver: hepatotoxic (but less than fluorothane),

Kidneys: decreased renal blood flow, skf, urine output.

Metabolism: a pronounced change in metabolism due to hyperglycemia, increased lactic acid, pyruvic acidosis.

In the postoperative period, vomiting is noted.

Nitrous oxide.

Immediate onset of anesthesia, without arousal stage. This is the effect of low plasma solubility. Because of this, a rapid awakening of the patient occurs. Penetrates quickly into the central nervous system. Used for pain relief in myocardial infarction, severe trauma, childbirth, etc. the main disadvantage: low drug activity. Therefore, it is necessary to combine with other anesthetic drugs. Should not be used for long-term analgesia.

In the postoperative period, nausea and vomiting may occur.

Respiration: does not irritate mucous membranes.

CVS: not accompanied by changes in heart function.

Liver: does not cause

Kidney: a transient decrease in urine output is due to constriction of the renal arteries, an increase in the production of ADH.

Metabolism: does not cause

Blood system: use of nitrous oxide for a long time may cause thrombocytopenia, agranulocytosis, megaloblastic anemia.