Cephalosporins

First Generation: GPC (except enterococci, MRSA, and coagulase-negative staphylococci), E. coli, Klebsiella pneumoniae, and Proteus mirabilis. Have limited action against other enteric gram-negative bacilli and anaerobes. Used for treating skin/soft tissue infections, UTIs, minor MSSA, and for surgical prophylaxis (cefazolin).

  • Cefadroxil (Duricef, Ultracef), 500 mg to 1 g PO q12h

  • Cephalothin (Keflin)

  • Cephapirin (Cefadyl)

  • Cephalexin (Keflex), 250-500 mg PO q6h

  • Cephradine (Velocef, Anspor)

  • Cefazolin (Ancef, Kefzol), 1-2 g IV/IM q8h (for surgical prophylaxis)

Second Generation: Less active against GPC than first-generation cephalosporins; more active against some gram-negative organisms such as H. influenzae, Enterobacter spp. and some Proteus spp. Can be divided into above-the-diaphragm and below-the-diaphragm agents.

  • Cefamandole (Mandol)

  • Cefoxitin (Mefoxin), 1-2 g IV q4-8h and cefotetan, 1-2 g IVq12h are useful for treatment below the diaphragm. These agents have reasonable activity against gram-negatives and aerobes, including B. fragilis, and are commonly used for intra-abdominal or gynecologic surgical prophylaxis and infections, including diverticulitis and PID.

  • Cefprozil

  • Cefuroxime (Zinacef), 1.5 g IV/IM q8h useful for infections above the diaphragm. Has good antistaphylococcal and antistreptococcal activity in addition to extended spectrum against gram-negative aerobes and can be used for skin/soft tissue infections, complicated UTIs, and some community acquired respiratory tract infections. It does not reliably cover Bacteroides fragilis.

  • Cefuroxime axetil, 250-500 mg PO q12h, cefprozil, 250-500 mg PO q12h, and Cefaclor (Ceclor), 250-500 mg PO q12 are oral agents typically used for bronchitis, sinusitis, otitis media, UTIs, local soft-tissue infections, and oral step-down therapy for pneumonia or cellulitis responsive to parenteral cephalopsorins.

  • Ceforanide (Precef)

  • Cefonicid (Monocid)

  • Loracarbef (Lorabid)

Third Generation: Expanded activity against Gram-negative rods and retain significant activity against streptococci and MSSA. They have moderate anaerobic activity but generally not against B. fragilis. Cefotaxime and Ceftriaxone have slightly less activity against GPC than first-generation cephalosporins. Ceftazidime and cefoperazone have even less activity against GPC, but are excellent antipseudomonal agents. Some of these agents have significant CNS penetration and are useful in the treatment of meningitis. They are not reliable in treatment of organisms that produce AmpC beta-lactamases. These pathogens should be treated empirically with carbapenems, cefepime, or FQs.

  • Moxalactam (Moxam)

  • Cefixime (Suprax)

  • Cefoperazone (Cefobid)

  • Ceftizoxime (Ceftizox)

  • Ceftazidime (Fortaz), 1-2 g IV/IM q8h may be used for treatment of infections caused by susceptible strains of P. aeruginosa.

  • Tazidine

  • Ceftriaxone (Rocephin), 1-2 g IV/IM q12 - 24 h and Cefotaxime (Claforan), 1-2 g IM/IV q4 - 12h are very similar to one another in spectrum and efficacy. Can be used as empiric therapy for pyelonephritis, UTI with sepsis, pneumonia, intra-abdominal infections (combined with metronidazole), gonorrhea, and meningitis. They can also be used for OM, septic arthritis, endocarditis, and soft tissue infections caused by susceptible organisms.

  • Cefipodoxime proxetil, 100-400 PO q12h. It can be used as single-dose therapy for uncomplicated gonorrhea. Cefdinir (Omnicef), 300 mg PO q12h, ceftibuten, 400 mg PO q24h, and cefditoren pivoxil, 200-400 mg PO q12h are PO, useful for treatment of bronchitis and complicated sinusitis, otitis media, and UTIs. These agents can be used as a step-down therapy for CAP.

  • Claforan

Fourth Generation:

  • Cefepime (Maxipime): active against gram positives (including MRSA) and gram negatives (including Pseudomonas); not effective against enterococcus. Cefepime, 500 mg to 2 g IV/IM q8-12h has excellent aerobic gram-negative coverage, including P. aeruginosia and other bacteria producing AmpC beta-lactamases. It's gram-positive is similar to ceftriaxone and cefotaxime. Used routinely for empiric therapy in febrile neutropenic patients. Used in treating infections caused by ABx resistant gram-negative bacteria and some infections caused by both gram-positive and gram-negative aerobes. Anti-anaerobic coverage should be added where aerobes are suspected.

Fifth Generation:

Ceftobiprole, is uniquely active against methicillin-resistant Staphylococcus aureus and E faecalis. Ceftobiprole additionally has a gram-negative spectrum of activity similar to cefepime.

Special considerations:

    • Rarely associated with anaphylaxis, AIN, anemia, and leukopenia.

    • PCN-allergic patients have 5% to 10% incidence of a cross-hypersensitivity reaction to cephalosporins. Should not be used in a patient with a reported severe PCN allergy (anaphylaxis, hives) without prior skin testing or desensitization, or both.

    • Prolonged therapy >2 wks is monitored with weekly Sr. Cr and CBC.

    • Ceftriaxone can cause biliary sludging requiring d/c of the medication.