Agents that kill or inhibit microorganisms such as bacteria, fungi, viruses or parasites【789199571224237†L74-L85】
Explanation
Antimicrobials encompass a broad group of substances that act against microbes. They include antibiotics for bacteria, antifungals for yeasts and moulds, antivirals for viruses and antiparasitics for protozoans and helminths. An antimicrobial can be a natural product such as a fungal metabolite, a semi‑synthetic derivative or a wholly synthetic chemical. These agents work by disrupting essential processes in microbial cells: some bind bacterial ribosomes to block protein synthesis, others inhibit cell wall formation or interfere with nucleic acid replication. Agents targeting viruses hinder stages of the viral life cycle such as entry or genome replication, whereas antiparasitic drugs may paralyse worms or block protozoan metabolism. Antimicrobials may be bactericidal, fungicidal or virucidal, killing the target organism, or they may be static, merely inhibiting growth so that host defences can clear the infection. Despite their benefits, overuse and misuse select for resistant strains, making antimicrobial stewardship essential.
Categories and examples
Different classes of antimicrobials are defined by their target organisms. Antibiotics include β‑lactams and macrolides and are used for diseases such as pneumonia or sepsis. Antifungals, such as azoles and polyenes, treat infections like candidiasis and aspergillosis. Antivirals suppress replication of viruses like influenza and HIV by inhibiting viral enzymes. Antiparasitic agents target protozoa and helminths; for example, nitroimidazoles treat amoebiasis and praziquantel eliminates tapeworms. Non‑therapeutic antimicrobials, such as disinfectants and antiseptics, are applied to surfaces or skin to prevent infection. Combination therapy may be used to broaden coverage or prevent emergence of resistance, for example using two antivirals for HIV.
Antimicrobials save countless lives but must be used judiciously to preserve their effectiveness and minimise development of resistance.
Related Terms: Antibiotics, Antifungals, Antivirals, Antiparasitic, Antiseptics