Lecture Notes: Drugs for Bacterial Infections

Introduction

• Bacterial infection treatment is a significant part of nursing care.
• Understanding drug classifications and effects is crucial.
• Terms: Pathogenicity (ability to cause infection) and Virulence (ability to produce disease in small numbers).

Pathogens and Infection Process

• Pathogens include viruses, bacteria, fungi, protozoa, and multicellular organisms.
• Invasiveness: pathogens grow rapidly, damaging tissues.
• Toxin formation: bacterial toxins disrupt normal cellular activity.

Bacteria Identification

• Identified by shape (bacilli, cocci, spirilla), oxygen use (aerobic, anaerobic), and cell wall size (gram-positive, gram-negative).
• Gram-positive: thick walls, retain violet stain (e.g., Staphylococcus).
• Gram-negative: thin walls, lose stain (e.g., E. coli).

Antibiotic Classifications

• Affect pathogen's structure, metabolism, and life cycle.
• Antibiotics: can be bacteriostatic (slow growth) or bactericidal (kill bacteria).

Resistance

• Pathogens can mutate, leading to resistance.
• Strategies to delay resistance: use specific drugs, restrict unnecessary use, prevent transmission, and prophylactic treatments.

Selecting Antibiotics

• Consider patient's immune status, infection site, past reactions, age, pregnancy, and genetics.
• Important to balance risk and therapeutic benefits.

Specific Antibiotic Classes

Penicillins

• First mass-produced antibiotic.
• Effective against gram-positive bacteria (e.g., streptococcus).
• Monitor for allergies and gut issues.

Cephalosporins

• Similar to penicillins.
• Broad spectrum, effective against gram-negative bacteria.
• Monitor kidney function.

Tetracyclines

• Broad spectrum, bacteriostatic.
• Avoid in pregnancy/children due to bone growth inhibition.
• Monitor for sunburn risk and gut issues.

Macrolides

• Alternative to penicillin, effective against specific infections.
• Monitor for ototoxicity and cardiotoxicity.

Aminoglycosides

• Reserved for serious infections, especially gram-negative.
• Monitor for nephrotoxicity and ototoxicity.

Fluoroquinolones

• Broad spectrum, used for UTIs and biological warfare exposure.
• Monitor for tendon rupture and hepatotoxicity.

Sulfonamides

• Inhibit folic acid production.
• Monitor for anemia and hypersensitivity.

Miscellaneous Antibiotics

• Include carbapenems, clindamycin, metronidazole, and vancomycin.
• Important for specific resistant infections like MRSA.

Conclusion

• Careful selection and monitoring of antibiotics is crucial.
• Prevention of resistance and monitoring adverse effects are key aspects of effective treatment.