Antimicrobial agents – This book covers the entire syllabus of “Pharmacology” prescribed by BNMC- for a diploma in nursing science & midwifery students. We tried to accommodate the latest information and topics. This book is an examination set up according to the teachers’ lectures and examination questions.
At the end of the book, previous questions are given. We hope in touch with the book students’ knowledge will be upgraded and flourish. The unique way of presentation may make your reading of the book a pleasurable experience.
Antimicrobial agents
Antimicrobial agents provide some of the most dramatic examples of the advances of modern medicine. Many infectious diseases once considered incurable and lethal are now amenable to treatment with a few doses of antibiotics.
Or,
Antimicrobial agent is a general term for drugs, chemicals, or other substances that either kill or slow the growth of microbes. Among the antimicrobial agents are antibacterial drugs, antiviral agents, antifungal agents, and antiparasitic drugs.
Classification of Antimicrobial Agents:
Antimicrobial drugs can be classified in many ways:
A. According to their chemical structure:
| Chemical structure | Name of drugs |
| Sulfonamides and related drugs | Sulfadiazine and others, Sulfones-Dapsone (DDS), Paraaminosalicylic acid (PAS). |
| Diaminopyrimidine | Trimethoprim, Pyrimethamine. |
| Quinolones | Nalidixic acid, Norfloxacin, Ciprofloxacin, Prulifloxacin |
| B-Lactam antibiotics | Penicillins, Cephalosporins, Monobactams, Carbapenems |
| Tetracyclines | Oxytetracycline, Doxycycline, etc. |
| Nitrobenzene derivative | Chloramphenicol |
| Aminoglycosides | Streptomycin, Gentamicin, Amikacin, Neomycin, etc. |
| Macrolide antibiotics | Erythromycin, Clarithromycin, Azithromycin, etc. |
| Nitrofuran derivatives | Nitrofurantoin, Furazolidone. |
| Nitroimidazoles | Metronidazole, Tinidazole, etc. |
| Nicotinic acid derivatives | Isoniazid, Pyrazinamide, Ethionamide. |
| Azole derivatives: | Miconazole, Clotrimazole, Ketoconazole, Fluconazole. |
| Others | Rifampin, Spectinomycin, Sod. fusidate, Cycloserine, Viomycin, Ethambutol, Thiacetazone, Clofazimine, Griseofulvin. |
B. According to mechanism of action:
| Mechanism of action | Name of the drugs |
| Inhibit cell wall synthesis | Penicillins, Cephalosporins, Cycloserine, Vancomycin, Bacitracin. |
| Cause leakage from cell membranes | Polypeptides Polymyxins, Colistin, Bacitracin. Polyenes Amphotericin B, Nystatin, Hamycin. |
| Inhibit protein synthesis | Tetracyclines, Chloramphenicol, Erythromycin, Clindamycin, Linezolid. |
| Cause misreading of m-RNA code and affect permeability | Aminoglycosides Streptomycin, Gentamicin, etc |
| Inhibit DNA gyrase | Fluoroquinolones-Ciprofloxacin and others. |
| Interfere with DNA function | Rifampicin |
| Interfere with DNA synthesis | Acyclovir, Zidovudine. |
| Interfere with intermediary metabolism | Sulfonamides, Sulfones, PAS, Trimethoprim, Pyrimethamine, Metronidazole. |
C. Type of organisms against which primarily active:
| Organism class | Name of drugs |
| Antibacterial | Penicillins, Aminoglycosides, Erythromycin, Fluoroquinolones, etc |
| Antifungal | Griseofulvin, Amphotericin B, Ketoconazole, etc. |
| Antiviral | Acyclovir, Amantadine, Zidovudine, etc. |
| Antiprotozoal | Chloroquine, Pyrimethamine, Metronidazole, Diloxanide, etc. |
| Anthelmintic | Mebendazole, Pyrantel, Niclosamide, Diethyl carbamazine, etc. |
D. According to mode of action:
| Bacteriostatic | Bactericidal |
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E. According to spectrum of activity
| Narrow spectrum | Broad spectrum |
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[Ref- Bennett, Brown/10/175-77 & A short text book of nursing and mats/Dr. Tanvir]
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