Cefaclor is a semisynthetic cephalosporin antibiotic for oral administration. As with other cephalosporins, the bactericidal action of Cefaclor results from inhibition of cell-wall synthesis. Cefaclor is indicated in the treatment of the following infections when caused by susceptible strains of the designated microorganisms: Otitis media caused by Streptococcus pneumoniae, Haemophilus influenzae, staphylococci, and Streptococcus pyogenes; Lower respiratory tract infections, including pneumonia, caused by Streptococcus pneumoniae, Haemophilus influenzae, and Streptococcus pyogenes; Pharyngitis and Tonsillitis, caused by Streptococcus pyogenes; Urinary tract infections, including pyelonephritis and cystitis, caused by Escherichia coli, Proteus mirabilis, Klebsiella spp., and coagulase-negative staphylococci; Skin and skin structure infections caused by Staphylococcus aureus and Streptococcus pyogenes. Adverse effects considered to be related to therapy with cefaclor are: Hypersensitivity reactions, Rarely, reversible hyperactivity, agitation, nervousness, insomnia, confusion, hypertonia, dizziness, hallucinations, somnolence and diarrhea. Patients receiving Cefaclor may show a false-positive reaction for glucose in the urine with tests that use Benedict's and Fehling's solutions and also with Clinitest® tablets. There have been reports of increased anticoagulant effect when Cefaclor and oral anticoagulants were administered concomitantly.

Ceftolozane is a novel a cephalosporin-class antibacterial drug. In combination with a beta-lactamase inhibitor tazobactam (ZERBAXA, ceftolozane/tazobactam ) ceftolozane, is currently indicated for the treatment of the adult patients with complicated intra-abdominal infections caused by designated Gram-negative and Gram-positive microorganisms and complicated urinary tract infections caused by certain Gram-negative bacteria, including those caused by multi-drug resistant Pseudomonas aeruginosa. To reduce the development of drug-resistant bacteria and maintain the effectiveness of ZERBAXA and other antibacterial drugs, ZERBAXA should be used only to treat infections that are proven or strongly suspected to be caused by susceptible bacteria. Safety and effectiveness in pediatric patients have not been established.

Ceftaroline fosamil is a 5th generation cephalosporin with an in vitro spectrum of activity including Streptococcus agalactiae, penicillin- and cephalosporin-resistant S. pneumoniae, S. pyogenes, methicillin-susceptible S. aureus and methicillin-resistant S. aureus, Haemophilus influenzae, Klebsiella oxytoca, K. pneumoniae and Moraxella catarrhalis. Ceftaroline fosamil (TAK-599 or PPI-0903), the prodrug of the active metabolite, ceftaroline, was synthesized by Takeda Pharmaceutical Co., Ltd and developed by Cerexa, Inc. and Forest Laboratories, Inc. It is currently approved by the FDA for the treatment of acute bacterial skin and skin structure infections (ABSSSI) and community-acquired bacterial pneumonia (CABP) in adults. Ceftaroline fosamil is marketed under the brand name TEFLARO®, indicated in adult and pediatric patients 2 months of age and older for the treatment of acute bacterial skin and skin structure infections (ABSSSI) caused by susceptible isolates of the following Gram-positive and Gram-negative microorganisms: Staphylococcus aureus (including methicillin-susceptible and ‑resistant isolates), Streptococcus pyogenes, Streptococcus agalactiae, Escherichia coli, Klebsiella pneumoniae, and Klebsiella oxytoca. TEFLARO is also indicated in adult and pediatric patients 2 months of age and older for the treatment of community-acquired bacterial pneumonia (CABP) caused by susceptible isolates of the following Gram-positive and Gram-negative microorganisms: Streptococcus pneumoniae (including cases with concurrent bacteremia), Staphylococcus aureus (methicillin-susceptible isolates only), Haemophilus influenzae, Klebsiella pneumoniae, Klebsiella oxytoca, and Escherichia coli. Ceftaroline provides in vitro bactericidal activity against methicillin-, vancomycin-, daptomycin-, and linezolid-resistant Gram-positive organisms and select Gram-negative pathogens. The pharmacodynamics of ceftaroline is similar to other β-lactam agents. Ceftaroline exhibits a favorable adverse effect profile and is generally well tolerated. The bactericidal action of ceftaroline is mediated through binding to essential penicillin-binding proteins (PBPs). Ceftaroline is bactericidal against S. aureus due to its affinity for PBP2a and against Streptococcus pneumoniae due to its affinity for PBP2x.

Cefdinir is an extended-spectrum, semisynthetic cephalosporin, for oral administration. As with other cephalosporins, bactericidal activity of cefdinir results from inhibition of cell wall synthesis. Cefdinir is stable in the presence of some, but not all, β-lactamase enzymes. Cefdinir is indicated for the treatment of: Community-Acquired Pneumonia, Acute Exacerbations of Chronic Bronchitis, Acute Maxillary Sinusitis, Pharyngitis/Tonsillitis and Uncomplicated Skin and Skin Structure Infections. Side effects include diarrhea, vaginal infections or inflammation, nausea, headache, and abdominal pain. Concomitant administration of 300-mg cefdinir capsules with 30 mL Maalox® TC suspension reduces the rate (Cmax) and extent (AUC) of absorption by approximately 40%. As with other β-lactam antibiotics, probenecid inhibits the renal excretion of cefdinir.

Cefepime is a fourth-generation cephalosporin antibiotic, which was developed in 1994. Cefepime has a broad spectrum in vitro activity that encompasses a wide range of Gram-positive and Gram-negative bacteria. Within bacterial cells, the molecular targets of cefepime are the penicillin binding proteins (PBP). It is FDA approved for the treatment of pneumonia, febrile neutropenia, uncomplicated UTI, uncomplicated skin infection and complicated intraabdominal infections. Common adverse reactions include rash, hypophosphatemia, diarrhea. Cefepime is metabolized to N-methylpyrrolidine (NMP) which is rapidly converted to the N-oxide (NMP-N-oxide). Urinary recovery of unchanged cefepime accounts for approximately 85% of the administered dose. Less than 1% of the administered dose is recovered from urine as NMP, 6.8% as NMP-N-oxide, and 2.5% as an epimer of cefepime. Because renal excretion is a significant pathway of elimination, patients with renal dysfunction and patients undergoing hemodialysis require dosage adjustment.

Cefpodoxime is an orally administered, extended spectrum, semi-synthetic antibiotic of the cephalosporin class. Cefpodoxime is a bactericidal agent that acts by inhibition of bacterial cell wall synthesis. Cefpodoxime has activity in the presence of some beta-lactamases, both penicillinases and cephalosporinases, of Gram-negative and Gram-positive bacteria. Cefpodoxime is indicated for the treatment of patients with mild to moderate infections caused by susceptible strains of the designated microorganisms in the conditions: acute otitis media; pharyngitis and/or tonsillitis; community-acquired pneumonia; acute bacterial exacerbation of chronic bronchitis; gonorrhea; uncomplicated skin and skin structure infections; acute maxillary sinusitis and uncomplicated urinary tract infections (cystitis). Common adverse reactions include diarrhea, nausea, vaginal fungal infections, vulvovaginal infections, abdominal pain, headache. Concomitant administration of high doses of antacids (sodium bicarbonate and aluminum hydroxide) or H2 blockers reduces peak plasma levels by 24% to 42% and the extent of absorption by 27% to 32%, respectively. Oral anti-cholinergics (e.g., propantheline) delay peak plasma levels (47% increase in Tmax), but do not affect the extent of absorption (AUC). Probenecid: As with other beta-lactam antibiotics, renal excretion of cefpodoxime was inhibited by probenecid and resulted in an approximately 31% increase in AUC and 20% increase in peak cefpodoxime plasma levels.

Cefixime, an antibiotic, is a third-generation cephalosporin like ceftriaxone and cefotaxime. Cefixime is highly stable in the presence of beta-lactamase enzymes. As a result, many organisms resistant to penicillins and some cephalosporins due to the presence of beta-lactamases, may be susceptible to cefixime. The antibacterial effect of cefixime results from inhibition of mucopeptide synthesis in the bacterial cell wall. Like all beta-lactam antibiotics, cefixime binds to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, causing the inhibition of the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that cefixime interferes with an autolysin inhibitor. Cefixime is sold under the brand name Suprax, indicated for the treatment of: Uncomplicated Urinary Tract Infections Otitis Media Pharyngitis and Tonsillitis Acute Exacerbations of Chronic Bronchitis Uncomplicated Gonorrhea (cervical/urethral)

Ceftazidime is a semisynthetic, broad-spectrum, beta-lactam antibiotic, used especially for Pseudomonas and other gram-negative infections in debilitated patients. Ceftazidime is used to treat lower respiratory tract, skin, urinary tract, blood-stream, joint, and abdominal infections, and meningitis. The drug is given intravenously (IV) or intramuscularly (IM) every 8–12 hours (two or three times a day), with dose and frequency varying by the type of infection, severity, and/or renal function of the patient. Injectable formulations of ceftazidime are currently nebulized "off-label" to manage Cystic Fibrosis, non-Cystic Fibrosis bronchiectasis, drug-resistant nontuberculous mycobacterial infections, ventilator-associated pneumonia, and post-transplant airway infections. Ceftazidime is generally well-tolerated. When side effects do occur, they are most commonly local effects from the intravenous line site, allergic reactions, and gastrointestinal symptoms. According to one manufacturer, in clinical trials, allergic reactions including itching, rash, and fever, happened in fewer than 2% of patients. Rare but more serious allergic reactions, such as toxic epidermal necrolysis, Stevens-Johnson syndrome, and erythema multiforme, have been reported with this class of antibiotics, including ceftazidime. Gastrointestinal symptoms, including diarrhea, nausea, vomiting, and abdominal pain, were reported in fewer than 2% of patients.

Cefaclor is a semisynthetic cephalosporin antibiotic for oral administration. As with other cephalosporins, the bactericidal action of Cefaclor results from inhibition of cell-wall synthesis. Cefaclor is indicated in the treatment of the following infections when caused by susceptible strains of the designated microorganisms: Otitis media caused by Streptococcus pneumoniae, Haemophilus influenzae, staphylococci, and Streptococcus pyogenes; Lower respiratory tract infections, including pneumonia, caused by Streptococcus pneumoniae, Haemophilus influenzae, and Streptococcus pyogenes; Pharyngitis and Tonsillitis, caused by Streptococcus pyogenes; Urinary tract infections, including pyelonephritis and cystitis, caused by Escherichia coli, Proteus mirabilis, Klebsiella spp., and coagulase-negative staphylococci; Skin and skin structure infections caused by Staphylococcus aureus and Streptococcus pyogenes. Adverse effects considered to be related to therapy with cefaclor are: Hypersensitivity reactions, Rarely, reversible hyperactivity, agitation, nervousness, insomnia, confusion, hypertonia, dizziness, hallucinations, somnolence and diarrhea. Patients receiving Cefaclor may show a false-positive reaction for glucose in the urine with tests that use Benedict's and Fehling's solutions and also with Clinitest® tablets. There have been reports of increased anticoagulant effect when Cefaclor and oral anticoagulants were administered concomitantly.

Cefoxitin is a cephamycin antibiotic often grouped with the second-generation cephalosporins. It is active against a broad range of gram-negative bacteria including anaerobes. The methoxy group in the 7a position provides cefoxitin with a high degree of stability in the presence of beta-lactamases, both penicillinases and cephalosporinases, of gram-negative bacteria. The bactericidal action of cefoxitin results from inhibition of cell wall synthesis.