3. Blockers of calcium channels for the treatment of hypertension. Classification. Mechanism of action. Side effects. Contraindications Comparative evaluation of drugs.

Derivatives	No additional properties	With additional properties
phenylalkylamine	Verapamil, diphril	Tiapamide, falipamide
dihydropyridine	Nifedipine, amlodipine, isradipine, nimodipine, felodipine	niguldipine
Benzodiazepine	diltiazem
Blockers of different chemical structures	Mibefradil (coronary selective, Does not reduce myocardial contractility, does not inhibit peristalsis)	bepridil

Mechanism of action: Class IV drugs selectively block slow Ca channels and Ca2 + current into myocardiocytes. Under physiological conditions, a slow Ca2 + current is involved only in depolarization of the sinus and atrioventricular nodes, but with arrhythmias it also appears in the altered myocardium of the atria and ventricles.

Among Ca antagonists, drugs of the verapamil and diltiazem groups have an antiarrhythmic effect. These drugs reduce the transmembrane resting potential and lengthen the refractory period, as a result conduction slows down and the automatism of the sinus node decreases, the mechanism of recurrent excitation in supraventricular tachyarrhythmias is suppressed.

Indications for use

- prevention and relief of supraventricular tachyarrhythmias.

Side effects

GENERAL +:

- verapamil: edema, constipation, gingival hyperplasia;

- diltiazem: dermatitis, increased liver enzymes, weakness.

Contraindications

GENERAL +:

- arrhythmias caused by glycoside intoxication.

4. Antibiotics of the cephalosporin group. Classification. Mechanism of action. The nature of the action. Spectrum of action. Indications for use. Side effects. Contraindications Comparative evaluation of drugs.

Classification: a) I generation (with high activity against G + bacteria): cefazolin, cephalothin, cefapirin, cefradine, cephalexin; b) Generation II (highly active against G-bacteria): cefamandol, cefuroxime, cefaclor, cefoxitin, cefmetazole c) generation III (highly active against Pseudomonas aeruginosa): cefotaxime, ceftazidime, cefoperazone, cefixime; d) IV generation (active against bacteroids and other anaerobes): cefpirome

Mechanism: inhibit the synthesis of peptidoglycan of the cell wall, inhibit the synthesis of murein. prevent the formation of peptide bonds due to transpeptidase. Nature: bactericidal action. I - act on gram (+) and some gram (-) and do not act on Pseudomonas aeruginosa, Proteus, bacteroids; II - act on gram (+) and some gram (-), proteus and enterobacteria, do not act on Pseudomonas aeruginosa; III - stronger by gram (-), penetrate the BBB; IV - act on gram (+), Pseudomonas aeruginosa, gram (-)

Spectrum: wide. Penicillinase resistant, but destroyed by beta-lactamase (I).

Indicationsi: urinary, respiratory tract infections; meningitis; prevention of septic complications during surgery; pyelonephritis, cystitis; streptococcal tonsillopharyngitis; exacerbation of chronic bronchitis; community-acquired pneumonia requiring hospitalization; community-acquired infections of the skin and soft tissues of mild to moderate severity; infections against the background of neutropenia and immunodeficiency states; sepsis

Side effects: allergies; kidney damage; diarrhea; bleeding; thrombocytopenia; dysbiosis; pseudomembranous colitis

Contraindications: hypersensitivity; pregnancy; breast-feeding; diseases of the gastrointestinal tract; bleeding

Cefazolin - penetrates the placental barrier, lasts 6-8 hours.

Cefuroxime - resistant to beta-lactamases, penetrates the BBB, lasts 6-8 hours.

Ceftriaxone - resistant to beta-lactamases, penetrates the BBB, acts for 24 hours.

Cefepim - resistant to beta-lactamases, penetrates the BBB, lasts 12 hours