Antibiotics, Antifungals, Antivirals, GI/GU, Infectious Disease | Q&A | Grade A
| 100% Correct (Verified Answers) – Nursing Program
Subject: NR 565 Advanced Pharmacology Final Exam – Antimicrobials (bactericidal/bacteriostatic, beta-
lactams, cephalosporins, fluoroquinolones, macrolides, sulfonamides), Antifungals, Antivirals, GI/GU
(GERD, PUD, IBS, diarrhea), and Infectious Disease treatments
Source: NR 565 Course Materials / Latest 2026/2027 NCLEX/HESI Pharmacology Blueprint
Format: Q&A Guide with Rationale
1: What is the definition of a bacteriostatic antibiotic?
Correct Answer: Kills the bacteria.
1. Bacteriostatic antibiotics inhibit bacterial growth and reproduction, relying on the host immune
system to eliminate the organisms.
2. They are effective in immunocompetent patients but may not be adequate in
immunocompromised hosts.
3. Common bacteriostatic drugs include tetracyclines, macrolides, clindamycin, and
sulfonamides.
2: What is the definition of a bactericidal antibiotic?
Correct Answer: Kills the bacteria and stops the growth or spread of the infection.
1. Bactericidal antibiotics directly kill bacteria, often by disrupting cell wall synthesis, DNA
replication, or protein synthesis.
2. They are preferred in life-threatening infections, endocarditis, meningitis, and neutropenic
patients.
3. Examples include beta-lactams, aminoglycosides, fluoroquinolones, and vancomycin.
3: What are examples of bacteriostatic drugs?
Correct Answer: Clindamycin, macrolides, sulfonamides, tetracyclines.
1. These antibiotics inhibit protein synthesis (clindamycin, macrolides, tetracyclines) or folate
synthesis (sulfonamides).
2. They require an intact host immune system for complete bacterial eradication.
3. Tetracyclines and macrolides are commonly used for respiratory and atypical infections.
,4: What are examples of bactericidal drugs?
Correct Answer: Aminoglycosides, beta-lactams, fluoroquinolones, metronidazole, streptogramins,
vancomycin.
1. Bactericidal drugs are preferred for serious infections where rapid bacterial killing is essential.
2. Beta-lactams inhibit cell wall synthesis; fluoroquinolones inhibit DNA replication;
metronidazole causes DNA damage.
3. Vancomycin is bactericidal against gram-positive organisms including MRSA.
5: What factors contribute to antimicrobial resistance?
Correct Answer: Not knowing if the patient had recent use of antibiotics, provider overuse of broad-
spectrum antibiotics, not performing susceptibility testing, age younger than 2 years or older than 65
years, daycare center attendance, exposure to young children, multiple medical comorbidities,
immunosuppression.
1. Antimicrobial stewardship programs aim to reduce resistance by limiting unnecessary broad-
spectrum antibiotics.
2. Recent antibiotic use selects for resistant organisms; susceptibility testing guides targeted
therapy.
3. Young children (daycare) and elderly have higher colonization with resistant organisms.
6: What are the subclasses of beta-lactam penicillins?
Correct Answer: Natural penicillins, aminopenicillins, anti-staphylococcal penicillins, extended
spectrum penicillins.
1. Natural penicillins (penicillin G/V) target streptococci and syphilis.
2. Aminopenicillins (ampicillin, amoxicillin) add gram-negative coverage.
3. Anti-staphylococcal (nafcillin, oxacillin) cover MSSA; extended-spectrum (piperacillin) cover
Pseudomonas.
7: What is the pharmacodynamic mechanism of beta-lactam penicillins?
Correct Answer: Inhibit biosynthesis of bacterial cell wall (beta-lactam ring).
1. Beta-lactam antibiotics bind to penicillin-binding proteins (PBPs), inhibiting transpeptidation
and cell wall cross-linking.
2. This leads to bacterial cell lysis and death, particularly during active cell division.
3. Resistance occurs via beta-lactamase enzymes that hydrolyze the beta-lactam ring.
8: What is first-line therapy for strep pharyngitis?
Correct Answer: Penicillin V.
1. Penicillin V is narrow-spectrum, inexpensive, and group A streptococcus remains universally
susceptible.
2. Amoxicillin is equally effective and tastes better for children.
3. Treatment prevents rheumatic fever and suppurative complications.
, 9: What is first-line therapy for all bites (animal and human)?
Correct Answer: Amoxicillin/clavulanate (Augmentin).
1. Bite wounds are polymicrobial, including Pasteurella (dogs/cats), anaerobes, and staph/strep.
2. Clavulanate provides beta-lactamase coverage against oral anaerobes and Pasteurella.
3. Alternatives include doxycycline or TMP-SMX plus clindamycin for penicillin-allergic
patients.
10: What are natural penicillin drugs?
Correct Answer: Penicillin V potassium (Ledercillin), Penicillin G sodium (PCN G-Na), Penicillin G
procaine (Duracillin), Penicillin G benzathine (Permapen), Penicillin G potassium (Pfizerpen).
1. Penicillin V is oral; Penicillin G is parenteral (IV/IM).
2. Benzathine penicillin G is long-acting IM for rheumatic fever prophylaxis and syphilis.
3. Procaine penicillin provides moderate IM duration with local anesthetic properties.
11: What organisms are natural penicillins active against?
Correct Answer: Aerobic gram-positive organisms.
1. Natural penicillins cover streptococcus species, enterococcus, and treponema pallidum
(syphilis).
2. They do NOT cover Staphylococcus aureus (penicillin-resistant) or most gram-negative
organisms.
3. Susceptibility should be confirmed for serious infections due to resistance.
12: What organisms are aminopenicillins active against?
Correct Answer: Gram-negative organisms.
1. Aminopenicillins cover H. influenzae, E. coli, Proteus, and Salmonella in addition to gram-
positive organisms.
2. However, many gram-negatives now produce beta-lactamases, rendering them resistant.
3. Adding a beta-lactamase inhibitor (clavulanate, sulbactam) restores activity against these
organisms.
13: What are aminopenicillin drugs?
Correct Answer: Amoxicillin, ampicillin; combinations: amoxicillin-clavulanate (Augmentin).
1. Amoxicillin is well-absorbed orally; ampicillin has poor oral absorption but good IV
bioavailability.
2. Augmentin combines amoxicillin with clavulanate to overcome beta-lactamase resistance.
3. Ampicillin-sulbactam (Unasyn) is the IV equivalent for hospitalized patients.