Table 126-3.
ANTIMICROBIAL DRUGS FOR CENTRAL NERVOUS SYSTEM INFECTIONS
| Drug | BBB Penetration | Bacteriocidal vs. Bacteriostatic | Dose (mg/kg) | Route | Frequency (hrs) | Antimicrobial Spectrum |
|---|---|---|---|---|---|---|
| Amphotericin B | Poor | Static | 0.15–0.50 | IV | 48 | Fungi (crypto) |
| Ampicillin | Intermediate | Cidal | 10–20 | IV | 6 | Broad (except BLRSE) |
| Cefotaxime | Good | Cidal | 20–50 | IV | 6 | Broad (except Salmonella) |
| Cefepime | Good | Cidal | 40–50 | IV | 6 | Broad (except Bacteroides, Clostridium, Enterobacter) |
| Ceftazidime | Good | Cidal | 15–30 | IV | 6–8 | Broad (except Enterococcus) |
| Ceftiofur | Poor to intermediate | Cidal | 2.2–4.4 | SQ | 12 | Broad (except Pseudomonas, |
| Enterococcus, Bacteroides, Bordetella) | ||||||
| Ceftriaxone | Good | Cidal | 15–50 | IV, IM, SQ | 12 | Broad (except Enterococcus, |
| Salmonella) | ||||||
| Ceftizoxime | Good | Cidal | 25–50 | IV | 8 | Broad (except Enterococcus, Pseudomonas) |
| Cefuroxime | Good | Cidal | 30 | IV | 8 | Broad (except BLRSE) |
| Cephalexin | Poor | Cidal | 20–30 | PO | 8 | Gm+ (except BLRSE) |
| Chloramphenicol | Good | Static | 25–50 | PO | 6–8 | Gm-(except Pseudomonas, Klebsiella), some Gm+ |
| Clavamox | Poor | Cidal | 10–20 | PO | 8–12 | Broad (except Pseudomonas, Enterococcus) |
| Clindamycin | Poor | Static/cidal | 12.5–20.0 | PO, IM | 12 | Gm+, anaerobes, protozoa |
| Doxycycline | Intermediate | Static | 5 | PO | 12 | Rickettsial |
| Enrofloxacin | Intermediate | Cidal | 5–10 | IV, SQ, PO | 12 | Gm- |
| Florfenicol | Good | Static | 25–50 | IM, SQ | 8 | Broad |
| Fluconazole | Good | Static | 5–10 | PO | 12–24 | Fungi (crypto) |
| Flucytosine | Intermediate | Static | 50 | PO | 6 | Fungi (crypto) |
| Gentamicin | Poor | Cidal | 2–4 | IV, IM | 8–12 | Gm- |
| Itraconazole | Poor | Static | 5 | PO | 12–24 | Fungi (crypto) |
| Ketoconazole | Poor | Static | 10–20 | PO | 12–24 | Fungi (crypto) |
| Metronidazole | Good | Cidal | 10–15 | PO | 8 | Anaerobes |
| Penicillin G | Poor to intermediate | Cidal | 20000–40000 U/kg | IV | 6 | Broad (except BLRSE) |
| Pyrimethamine | Good | Cidal | 1 (cats: 0.25–1.00) | PO | 24 | Protozoa |
| Rifampin | Good | Cidal | 10–20 | IV | 24 | Gm+, Chlamydia |
| Tetracycline | Intermediate | Static | 22 | PO | 8 | Rickettsial |
| Trimethoprim-sulfadiazine | Good | Cidal | 15–30 | PO, SQ | 12 | Broad (except Pseudomonas, anaerobes), protozoa |
| Vancomycin | Poor to intermediate | Cidal | 15 | IV | 6 | Gm+, BLRSE (except Gm-) |
BBB, blood-brain barrier; BLRSE, beta-lactamase–resistant Staphylococcus and Enterococcus species; Broad, broad spectrum including Gm+, Gm-, and anaerobic bacteria; IM, intramuscularly; IV, intravenously; PO, per os; SQ, subcutaneously.