Meropenem
Merrem
Carbapenem β-lactam (broad-spectrum, antipseudomonal)
Broad gram-positive/negative/anaerobic + Pseudomonas coverage. LOWER seizure potential than imipenem.
Indications
- •Severe/resistant infections, febrile neutropenia, meningitis (CNS penetration), intra-abdominal sepsis
Dosing
| Context | Adult | Pediatric |
|---|---|---|
| Serious infection | 1 g IV q8h (2 g q8h for meningitis; renally adjusted) | — |
Pharmacokinetics
Half-life ~1 h. Renally cleared.
Side effects
- !Seizure (less than imipenem)
- !C. difficile
- !β-lactam allergy
- !LOWERS valproate levels (loss of seizure control)
Contraindications
- ×Severe β-lactam allergy
Clinical pearls
- ★Preferred carbapenem for CNS infection (lower seizure risk than imipenem, good CSF penetration).
- ★Dramatically lowers valproate levels — avoid the combination in seizure patients.
Other drugs in Antibiotics
- Cefazolin
β-lactam — inhibits bacterial cell wall PBPs.
- Vancomycin
Inhibits cell wall synthesis (binds D-Ala-D-Ala). Active against MRSA + gram-positives.
- Clindamycin
Binds 50S ribosomal subunit, blocks peptide-bond formation. Bacteriostatic against most organisms; bactericidal against susceptible streptococci. Excellent activity against anaerobes and gram-positive cocci including community-acquired MRSA.
- Gentamicin
Binds 30S ribosomal subunit, causes misreading of mRNA → defective bacterial protein synthesis. Bactericidal, concentration-dependent killing. Synergy with cell-wall agents (β-lactams, vancomycin) for gram-positive endocarditis.
- Cefuroxime
β-lactam — inhibits cell-wall synthesis (PBP binding). 2nd-gen: gram-positive + expanded gram-negative.
- Cefepime
β-lactam cell-wall inhibitor. Broad gram-negative (incl. Pseudomonas) + gram-positive coverage.
- Cefotetan
β-lactam; adds anaerobic (B. fragilis) coverage → colorectal/gynecologic prophylaxis.
- Cefotaxime
β-lactam cell-wall inhibitor. Broad gram-negative + CNS penetration.
Browse all classes: /reference/drugs
Suggested reading
- •Miller's Anesthesia, 9e
- •FDA package insert
