Types of Antibacterials and Client Teaching

Types of Antibacterials

• Beta-lactams: Includes Penicillins, Cephalosporins (5 generations), and Carbapenems.
• Aminoglycosides: End in “-mycin” or “-micin.”
• Fluoroquinolones: End in “-floxacin.”
• Tetracyclines: End in “-cycline.”
• Sulfonamides: Often start with “sulfa-.”
• Macrolides: End in “-thromycin.”
• Ketolides: A newer class of antimicrobials.
• Urinary Antiseptics: Specific to urinary infections.
• Miscellaneous drugs: Various other antibacterial agents.

Universal Client Teaching for Anti-infective Therapy

• Maintain regular dosing schedules; do not skip doses or double doses.
• Complete the entire course of medication even if symptoms improve.
• Dispose of any unused medication and do not use past expiration dates.
• Consult healthcare providers before taking over-the-counter medications.
• Monitor for signs of superinfections (e.g., secondary infection after antibiotic treatment).

Penicillins

• Mechanism: Weaken bacterial cell walls, leading to bacterial rupture; effective only during active growth.
• Bactericidal effect: Primarily active against bacteria that are dividing.
• Resistance: Can occur due to target reach failure, enzyme inactivation, or altered penicillin-binding proteins.

Penicillin Allergy

• Allergic reactions can occur and should be assessed prior to administration.
• Skin tests available to detect allergies.
• Patients with a history of mild reactions may use cephalosporins; avoid penicillins or cephalosporins in anaphylaxis cases.

Classification of Penicillins

• Narrow-spectrum penicillins:
  • Penicillinase-sensitive (Penicillin G, V)
  • Penicillinase-resistant (Dicloxacillin, Nafcillin, Oxacillin)
• Broad-spectrum penicillins: Aminopenicillins (Amipicillin, Amoxicillin, Ticarcillin, Piperacillin).

Common Adverse Effects of Penicillins

• Hypersensitivity reactions and gastrointestinal disturbances (diarrhea, N/V).
• Drug interaction caution: Penicillin can inactivate IV aminoglycosides (gentamycin).
• Cross-sensitivity noted with cephalosporins and carbapenems.

Penicillin-Beta-Lactamase Inhibitor Combinations

• Include beta-lactamase inhibitors to prevent antibiotic inactivation.
• Examples: Unasyn, Augmentin, Zosyn, Timentin.

Cephalosporins ("cef-")

• Most widely used antibiotics; classified into 5 generations.
• Disrupt cell wall synthesis; typically bactericidal.
• Greater activity against gram-negative bacteria.

Classification of Cephalosporins

• First generation: Cefazolin (Ancef), primarily for prophylaxis.
• Second generation: Cefaclor, Cefotetan.
• Third generation: Cefoperazone, Ceftriaxone (used for serious infections).
• Fourth generation: Cefepime.
• Fifth generation: Ceftaroline (targeting MRSA and VRE).

Adverse Effects of Cephalosporins

• Common: Hypersensitivity reactions, GI complaints, risk of superinfections.
• Caution with anticoagulant patients (may decrease Vitamin K).

Carbapenems ("-penem")

• Broad-spectrum, bactericidal, used for multi-drug resistant infections.
• Not typically absorbed from the GI tract; must be administered parenterally.
• Examples include Imipenem-cilastatin and meropenem.
• Adverse effects: GI disturbances, hypersensitivity, risk of superinfections.

Vancomycin (Vancocin, Vancoled)

• Inhibits cell wall synthesis; considered bactericidal.
• Effective against severe infections like MRSA.
• Side effects include ototoxicity, nephrotoxicity, and red man syndrome.
• Monitoring of peak and trough levels is necessary.

Aminoglycosides ("-micin" or "-mycin")

• Bactericidal; primarily target aerobic gram-negative bacteria.
• Known for potential toxicity to kidneys and inner ear; low therapeutic index.
• Must monitor serum levels and renal function.
• Common agents include Gentamicin, Tobramycin, and Streptomycin.

Fluoroquinolones ("-floxacin")

• Broad-spectrum, disrupt DNA synthesis.
• Administerable via oral or IV; not recommended for those under 18.
• Side effects include tendon rupture, photosensitivity, and CNS effects.
• Ciprofloxacin: Specific uses include treatment of anthrax; affected by various antacids and supplements.

Tetracyclines ("-cycline")

• Broad-spectrum, inhibit protein synthesis; bacteriostatic.
• Increasing bacterial resistance noted; uses include specific infections like Rickettsial diseases and acne.
• Absorption affected by chelation with calcium, iron, and antacids.
• Adverse effects include gastrointestinal irritation and impact on bone/teeth; avoid in children.