Chapter 9: Antibacterial Drugs That Interfere With DNA/RNA Synthesis

Learning Objectives

  • Explain:

    • Uses, general drug actions, contraindications, precautions, interactions, and adverse reactions of antibacterial drugs that interfere with DNA/RNA synthesis.

  • Distinguish:

    • Pre-administration and ongoing assessment activities the nurse should perform on the client taking an antibacterial drug that interferes with DNA/RNA synthesis.

  • List:

    • Nursing diagnoses particular to a client receiving an antibacterial drug that interferes with DNA/RNA synthesis.

  • Examine:

    • Ways to promote an optimal response to therapy, how to manage adverse reactions, and important points to keep in mind when educating clients about the use of antibacterial drugs that interfere with DNA/RNA synthesis.

    • SLOs: Safety, Patient-Centered Care, Evidence-based Practice.

Antibiotics That Interfere With DNA/RNA Synthesis

  • Classes involved:

    • Fluoroquinolones and Rifampin

  • Mechanisms of interference:

    • Affect mRNA and DNA synthesis by inhibiting the enzymes required for these processes.

  • Cell Wall Synthesis Inhibitors:

    • Involves penicillins, cephalosporins, and other similar drugs.

  • Protein Synthesis Inhibitors:

    • Includes tetracyclines, aminoglycosides, macrolides, and lincosamides, as well as sulfonamides.

Antibiotic Stewardship

  • Superinfections:

    • Occurs when antibiotics disrupt normal flora resulting in secondary infections, commonly referred to as superinfections.

    • Frequently linked to C. difficile, a major cause of antibiotic-related diarrhea in long-term care (LTC) facilities.

  • Antibiotic Stewardship Programs:

    • Implemented in nursing homes to reduce inappropriate antibiotic prescriptions and mitigate antibiotic overuse.

  • Types of Superinfections:

    • C. difficile and Candidiasis (moniliasis).

Fluoroquinolones

  • Actions:

    • Exhibits a bactericidal effect by interfering with bacterial enzyme synthesis, incapacitating bacterial DNA formation, and consequently leading to cell reproduction prevention and bacterial cell death.

Uses

  • Employed to treat infections caused by both gram-negative and gram-positive microorganisms, including:

    • Lower Respiratory Tract Infections

    • Bone and Joint Infections

    • Urinary Tract Infections

    • Infections of the Skin

    • Sexually Transmitted Infections

  • Specific Ophthalmic Forms:

    • Ciprofloxacin and Ofloxacin for treating eye infections.

Adverse Reactions

  • Common Adverse Reactions:

    • Nausea

    • Diarrhea

    • Headache

    • Abdominal pain or discomfort

    • Dizziness

    • Photosensitivity

  • Serious Adverse Effects:

    • Aortic dissection or rupture

    • Hypersensitivity

    • Risk of bacterial or fungal superinfections.

Contraindications

  • Not suitable for clients:

    • With a history of hypersensitivity

    • Younger than 18 years

    • Pregnant individuals (Pregnancy Category C)

  • Use with caution in clients with:

    • Diabetes

    • Renal impairment

    • Previous seizures

    • Geriatric clients (increased risk of tendonitis and tendon rupture)

    • Those on dialysis.

Interactions

  • Interacting Drugs:

    • Theophylline: May raise serum theophylline levels.

    • Cimetidine: Interferes with the elimination of the fluoroquinolone.

    • Oral Anticoagulants: Heightens bleeding risks.

    • Antacids, Iron Salts, and Zinc: Causes decreased antibiotic absorption.

    • NSAIDs: May increase seizure risk.

    • Drugs prolonging QT interval (e.g. Quinidine, Procainamide, Amiodarone, Sotalol): Risk of severe cardiac arrhythmias.

    • Corticosteroids: Heightened risk of tendinitis and tendon rupture.

Summary Drug Table

  • Antibacterial Drugs That Interfere With DNA/RNA Synthesis:

    • Generic Name:

    • Fluoroquinolones

    • Trade Name and Uses:

    • Ciprofloxacin: Treatment of bone, joint, GI, GU infections caused by susceptible microorganisms

    • Delafloxacin (Baxdela): Bronchitis, pneumonia, soft tissue infections

    • Gemifloxacin: Treatment of similar conditions as ciprofloxacin

    • Levofloxacin: Similar to ciprofloxacin

    • Moxifloxacin (Avelox): Same as ciprofloxacin

    • Ofloxacin: Same as ciprofloxacin

    • Adverse Reactions:

    • Nausea, diarrhea, headache, abdominal discomfort, photosensitivity, superinfections, hypersensitivity reactions.

    • Dosage Ranges:

    • Varies by drug, e.g., 250-750 mg orally every 12 hours; specific dosages for others mentioned.

    • Miscellaneous Drugs That Inhibit RNA/DNA Synthesis:

    • metronidazole (Flagyl): Treatment of anaerobic infections

    • rifaximin: Treatment of hepatic encephalopathy, IBS, C. difficile infection.

Pre-admission Assessment

  • Objective Data:

    • Signs of infection: drainage, redness, sputum appearance, cough, swelling

    • Vital signs

    • Culture and sensitivity results

    • Renal and hepatic function tests, CBC, urinalysis if history of impaired function.

  • Subjective Data:

    • Client-reported symptoms: pain, malaise, fatigue

    • Allergy history

    • History of heart, renal, hepatic issues, and previous seizure activity.

Ongoing Assessment

  • Monitor vital signs every 4 hours or as ordered and report significant changes.

  • Compare current vs. baseline signs and symptoms of infection and document any specific findings.

Planning

  • Expected client outcomes include:

    • Control of the infectious process or prophylactic measures against bacterial infection

    • Management of any adverse drug effects

    • Patient confidence and comprehension regarding the treatment regimen.

Implementation

Promoting an Optimal Response to Therapy

  • Observe for adverse reactions within the first 48 hours of treatment.

  • Report any adverse reactions to the healthcare provider.

  • Discuss and document any complaints from clients; may indicate early adverse reactions.

  • Advise clients to increase fluid intake.

Special Administration Instructions

  • Norfloxacin: Administer on an empty stomach (1 hour before or 2 hours after meals).

  • Extended release or controlled release drugs: Instruct clients to swallow whole, do not crush or chew.

  • For clients taking antacids, Ciprofloxacin and Moxifloxacin should be spaced by 2 to 4 hours before or 6 to 8 hours after taking antacid.

Monitoring and Managing Client Needs

Nursing Diagnosis 1: Risk for Impaired Comfort Related to Fever

  • Monitor temperature regularly.

  • For elevated temperature (>101°F), notify the healthcare provider, recheck vitals hourly until normal; administer antipyretics if prescribed.

Nursing Diagnosis 2: Impaired Skin Integrity

  • Monitor for photosensitivity.

  • Advise use of sunscreen and protective clothing.

Nursing Diagnosis 3: Parenteral Administration – Acute Pain: Tissue Injury

  • Inspect IV site for signs of extravasation, tenderness, redness.

  • Check infusion rate every 15 minutes.

  • Assess IV vein every 4 to 8 hours; restart IV if symptoms arise.

Nursing Diagnosis 4: Diarrhea

  • Monitor for and report symptoms of superinfection starting usually 4 to 10 days post-treatment.

  • Inspect stools for blood and mucus, notify provider of abnormalities.

Superinfection Education

  • Client Teaching for Improved Outcomes:

    • Antibiotics increase the risk of superinfection; recognize signs and symptoms.

    • Common superinfection signs include:

    • Fever

    • Burning sensation in the mouth or throat

    • Localized inflammation, particularly inside the mouth and in skin folds

    • Abdominal cramps and severe diarrhea.

    • Fungal superinfection signs: creamy patches in the mouth or yellow vaginal discharge.

  • Sequence for superinfection development during anti-infective therapy:

    1. Secondary infection follows primary infection.

    2. Uncontrolled bacterial growth occurs.

    3. Antibiotics disrupt bowel normal flora.

    4. Symptoms like cramping and bleeding may occur.

    5. Toxins produced by microorganisms.

Educating the Client and Family

  • Develop a plan including:

    • Explanation of adverse reactions related to specific antibiotics.

    • Awareness of serious adverse effects: fever, rash, diarrhea, and signs of possible fungal infections.

Evaluation

  • Assess whether therapeutic effects were achieved (infection controlled).

  • Were adverse reactions identified, reported, and managed?

  • Verification of client comfort and absence of fever.

  • Skin integrity evaluation (free from inflammation or infection).

  • Ensure client understanding and confidence in drug regimen.