Antibiotics: Understanding their Classifications

About this course

In the United States, 236 million outpatient antibiotic prescriptions are dispensed annually, with penicillin, macrolides, and cephalosporins being among the most used. Despite their remarkable benefits, antibiotics have also brought about unforeseen challenges. Misuse and overuse of these compounds have fueled the emergence of antibiotic resistance, rendering some infections virtually untreatable. This course provides a comprehensive overview of antibiotics, their classifications, mechanisms of action, and selection criteria. Antibiotic resistance, side effects, and nursing considerations will also be examined to equip healthcare professionals with the necessary skills and understanding to optimize antibiotic therapy while minimizing risks and promoting patient safety.

Learning objectives

• Review how antibiotics are selected to combat infections.
• Differentiate between bactericidal and bacteriostatic antibiotics and their pharmacodynamic and pharmacokinetic properties.
• Recognize the importance of taking antibiotics in completion, and as prescribed.
• Review antibiotic resistance, and the three primary mechanisms how resistance genes can be transferred.
• Identify side effects and allergic reactions commonly associated with antibiotics.

Course outline

15 sections · finish in any order across devices

1. 1

   Introduction

   For millennia, humanity has used antibiotics to treat infections, going as far back as the ancient Egyptians, who employed various molds and plant extracts to treat wound infections. However, it was not until centuries later, with the groundbreaking discovery of penicillin in 1928, that scientists b

   4 min

2. 2

   Defining Antibiotics

   Antibiotics are a class of antimicrobial drugs primarily used to treat bacterial infections. They can be derived from bacteria, fungi, or molds or be synthesized artificially. Also known as antibacterial drugs, these medications affect infection-causing bacteria through various mechanisms, including

   4 min

3. 3

   Antibiotic Selection

   When selecting the appropriate antibiotics, cultures and antibiotic susceptibility testing play a crucial role in treating severe infections. Based on this information, the general principle is to opt for drugs with the narrowest spectrum of activity that can effectively control the infection in the

   4 min

4. 4

   Benefits of Use

   Antibiotics offer several key benefits in treating bacterial infections, often making them preferable to relying solely on the body's natural defense mechanisms, especially when the immune system is compromised, or the infection is particularly aggressive. In such cases, antibiotics provide a target

   4 min

5. 5

   Types of Antibiotics

   Antibiotics are classified into two primary categories based on their effects on bacteria: 8,9

   4 min

6. 6

   Bactericidal Antibiotics that Inhibit Cell Wall Synthesis

   Bactericidal antibiotics that inhibit cell wall synthesis prevent bacteria from constructing and maintaining a protective outer covering, compromising its integrity and eventually leading to bacterial death. Within this class, antibiotics are either beta-lactam or non-lactam. Beta-lactam antibiotics

   4 min

7. 7

   Beta-Lactam Bactericidal Antibiotics

   Penicillin, discovered in 1929 and clinically introduced in 1943, represents the first natural antibiotics isolated. Derived from fungi, penicillin targets cell wall synthesis by binding to penicillin-binding proteins. Penicillins primarily target gram-positive bacteria and certain gram-negative coc

   4 min

8. 8

   Non-Lactam Bactericidal Antibiotics

   Glycopeptides are potent antibiotics derived from actinomycetes. Currently, vancomycin is the only glycopeptide available for clinical use. Glycopeptides target cell wall synthesis, particularly the D-Ala-D-Ala termini of lipid II and is effective against a broad range of gram-positive cocci and bac

   4 min

9. 9

   Bactericidal Antibiotics That Inhibiting Bacterial Enzymes or Protein Translation

   Bactericidal antibiotics that inhibit bacterial enzymes or protein translation disrupt essential enzymatic reactions or protein synthesis pathways vital for bacterial survival and reproduction, ultimately leading to bacterial death. This category includes fluoroquinolones, mupirocin, sulfonamides, a

   4 min

10. 10

    Bacteriostatic Antibiotics

    Bacteriostatic antibiotics prevent bacterial growth and reproduction but do not necessarily kill bacteria. Bacteriostatic antibiotics do this by interfering with bacterial protein production, DNA replication, or other aspects of bacterial cellular metabolism. They work with the immune system to remo

    6 min

11. 11

    Taking Antibiotics as Prescribed

    Proper use of antibiotics is paramount to ensure their value in treating bacterial infections while minimizing the risk of adverse effects and antibiotic resistance. When prescribed antibiotics, it is crucial to adhere to the instructions provided by healthcare providers or pharmacists. Instructions

    4 min

12. 12

    Antibiotic Resistance

    Antibiotic resistance is the ability of bacteria to withstand the effects of antimicrobial drugs that were previously effective against them. These microorganisms evolve and adapt in ways that render antibiotics less effective or completely ineffective in killing or inhibiting their growth. Resistan

    4 min

13. 13

    Side Effects and Allergic Reactions

    Antibiotics, while effective in treating bacterial infections, can also cause side effects, adverse reactions, and allergic reactions in some individuals. Reactions can range from mild to severe and may vary depending on the type of antibiotic and individual patient factors. Mild side effects includ

    4 min

14. 14

    Nursing Considerations

    Nursing considerations play a crucial role in ensuring the safe and effective use of antibiotics and encompass a wide array of responsibilities, including antibiotic administration, monitoring, and patient education. This involves diligent observation of vital signs, laboratory values, and localized

    4 min

15. 15

    Conclusion

    Antibiotics are indispensable agents in the management of bacterial infections, offering a diverse array of mechanisms to combat microbial pathogens. Types of antibiotics, including bactericidal to bacteriostatic antibiotics target various aspects of bacterial physiology, disrupting essential proces

    4 min

This course satisfies

Requirement summaries come from our state requirement records. Always confirm details with your board before you renew.

References and resources

• Hutchings, M. I., Truman, A. W., & Wilkinson, B. (2019). Antibiotics: Past, present and future. Current Opinion in Microbiology, 51, 72-80. https://doi.org/10.1016/j.mib.2019.10.008
• All Antibiotic Classes | A.R. & Patient Safety Portal. (n.d.). Arpsp.cdc.gov. https://arpsp.cdc.gov/profile/antibiotic-use/all-classes
• Overview of Antibiotics - Infections. (n.d.). Merck Manuals Consumer Version. https://www.merckmanuals.com/home/infections/antibiotics/overview-of-antibiotics
• Leekha, S., Terrell, C. L., & Edson, R. S. (2011). General Principles of Antimicrobial Therapy. Mayo Clinic Proceedings, 86(2), 156-167. https://doi.org/10.4065/mcp.2010.0639
• Hayhoe, B., Butler, C. C., Majeed, A., & Saxena, S. (2018). Telling the truth about antibiotics: Benefits, harms and moral duty in prescribing for children in primary care. Journal of Antimicrobial Chemotherapy, 73(9), 2298-2304. https://doi.org/10.1093/jac/dky223
• Shah, N. B., Hersh, B. L., Kreger, A., Sayeed, A., Bullock, A. G., Rothenberger, S. D., Klatt, B., Hamlin, B., & Urish, K. L. (2020). Benefits and Adverse Events Associated With Extended Antibiotic Use in Total Knee Arthroplasty Periprosthetic Joint Infection. Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America, 70(4), 559-565. https://doi.org/10.1093/cid/ciz261
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• 13.1E: Antibiotic Classifications. (2018, June 25). Biology LibreTexts. https://bio.libretexts.org/Bookshelves/Microbiology/Microbiology_(Boundless)/13%3A_Antimicrobial_Drugs/13.01%3A_Overview_of_Antimicrobial_Therapy/13.1E%3A_Antibiotic_Classifications
• Werth,Brian. (2018). Penicillins. Merck Manuals Professional Edition; Merck Manuals. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/penicillins
• Werth,Brian. (2018). Cephalosporins. Merck Manuals Professional Edition; Merck Manuals. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/cephalosporins
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• ‌Simeis, D. D., & Serra, S. (2021). Actinomycetes: A Never-Ending Source of Bioactive Compounds—An Overview on Antibiotics Production. Antibiotics, 10(5). https://doi.org/10.3390/antibiotics10050483
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• Werth,Brian. (2019). Fosfomycin. Merck Manuals Professional Edition; Merck Manuals. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/fosfomycin
• Fluoroquinolones - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/fluoroquinolones
• Mupirocin - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. Retrieved February 16, 2024, from https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/mupirocin
• Metronidazole and Tinidazole - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/metronidazole-and-tinidazole
• ‌Nitrofurantoin - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/nitrofurantoin
• ‌Rifamycins - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/rifamycins
• ‌Sulfonamides - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/sulfonamides
• Aminoglycosides - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/aminoglycosides
• Tetracyclines - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/tetracyclines
• Macrolides - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/macrolides
• Lincosamides, Oxazolidinones, and Streptogramins - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/lincosamides,-oxazolidinones,-and-streptogramins
• Quinupristin and Dalfopristin - Infectious Diseases. (n.d.). Merck Manuals Professional Edition. Retrieved February 16, 2024, from https://www.merckmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/quinupristin-and-dalfopristin
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• CDC. (2021, January 13). Are you using antibiotics wisely? Centers for Disease Control and Prevention. https://www.cdc.gov/antibiotic-use/do-and-dont.html

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