Pharm 2 Final: Protein Synthesis Inhibitors, Quinolones & Antifolates

Gentamycin

MOA: Aminoglycoside; inhibits bacterial protein synthesis. Use: Aerobic gram-negative bacilli including Pseudomonas; combined with penicillin for endocarditis. SE: Nephrotoxicity and ototoxicity.

Doxycycline

MOA: Tetracycline; inhibits bacterial protein synthesis. Use: Gram-positive and gram-negative respiratory infections, pneumonia. Has MRSA activity (MRSA cellulitis). SE: N/A.

Azithromycin

MOA: Macrolide; inhibits bacterial protein synthesis. Use: Sinusitis, otitis media, bronchitis; single-dose treatment for chlamydia. SE: N/A.

Erythromycin

MOA: Macrolide; inhibits bacterial protein synthesis. Use: Topical treatment of conjunctivitis. SE: N/A.

Clindamycin

MOA: Macrolide; inhibits protein synthesis; activity against gram-positives and anaerobes. Use: Gram-positive and anaerobic infections. SE: Associated with C. difficile superinfections; multiple-day dosing to mitigate.

Mupirocin (Bactroban)

MOA: Inhibits bacterial protein synthesis. Use: Topical treatment of superficial infections. SE: N/A.

Neomycin

MOA: Aminoglycoside; used in triple therapy with Bacitracin and Polymyxin. Use: Topical treatment of superficial infections. SE: Most nephrotoxic aminoglycoside.

Trimethoprim-Sulfamethoxazole (Bactrim)

MOA: Anti-folate drugs with synergistic activity. Use: UTIs, Pneumocystis jiroveci pulmonary infections; MRSA coverage. SE: Check renal function for dose adjustment; monitor potassium for hyperkalemia.

Ciprofloxacin

MOA: Fluoroquinolone; inhibits bacterial DNA synthesis. Use: Bacterial diarrhea, UTIs, bone and joint infections. SE: FDA black box warning for tendinopathies; QTc prolongation; lowers seizure threshold; can cause delirium in elderly.

Levofloxacin

MOA: Fluoroquinolone; inhibits bacterial DNA synthesis. Use: Bronchitis/CAP, UTIs. SE: Same as ciprofloxacin.

Nitrofurantoin (Macrobid)

MOA: Inhibits bacterial enzymes. Use: Lower urinary tract (bladder) infections (cystitis only). SE: Requires renal function for drug delivery to bladder; avoid if CrCl <50 ml/hr.

Rifaximin

MOA: Decreases colonic bacteria and ammonia production (in hepatic encephalopathy). Use: Traveler's diarrhea, hepatic encephalopathy. SE: N/A.

Metronidazole (Flagyl)

MOA: Inhibits DNA synthesis by causing strand breakage. Use: Gram-positive, gram-negative, and anaerobic organisms; primary indication is C. difficile. SE: Can be given PO or IV.