Penicillin類抗生素

Bloodstream infection: caused by susceptible gram-positive organisms, including Streptococcus species, penicillin G-susceptible staphylococci, and enterococci; gram-negative bloodstream infection caused by E. coli, P. mirabilis, and Salmonella species.
Endocarditis, treatment: caused by susceptible gram-positive organisms, including Streptococcus species, penicillin G-susceptible staphylococci, and enterococci
GI infections: caused by S. typhi (typhoid fever), other Salmonella species, and Shigella species (dysentery).
Note: Ampicillin is not recommended as a first-line agent for shigellosis, salmonellosis (nontyphoid), or S. enterica species (typhoid fever) due to development of resistance
Meningitis, bacterial: caused by E. coli, group B streptococci, and other gram-negative bacteria (Neisseria meningitidis)
Respiratory tract infections: caused by S. pneumoniae, S. aureus, H. influenzae, and group A beta-hemolytic streptococci
Urinary tract infections: caused by E. coli and P. mirabilis

Antibiotic, Penicillin
Ampicillin is a semisynthetic penicillin (beta-lactam antibiotic) that shares the same mechanism of action as the other penicillins. It works by inhibiting bacterial cell-wall synthesis through binding to one or more penicillin bind proteins of actively dividing cells.

Absorption Tmax, IV: 2 hours following 500 mg bolus
Distribution Protein binding: 20%
Excretion Renal: 40% to 92% unchanged
Elimination Half Life: 1-1.9hr (normal patients), 4 to 5 hours (renal failure), 15 to 20 hours (oliguria), 2 to 4 hours (newborn), up to 6 hours (premature infant)

Not to be used in patients sensitive to penicillins.

B; Based on available data, penicillin antibiotics are generally considered compatible for use during pregnancy

Ampicillin is considered compatible with breastfeeding when used in usual recommended doses

Allergic reaction, skin rashes, urticaria, maculopapular, diarrhea, nausea, vomiting, raised serum aminotransferase, pseudomembranous colitis, superinfections with Pseudomonas and Candida

Bloodstream infection:
1. For Enterococcus spp.: 2 g every 4 hours for 7-14 days; use as part of an appropriate combination regimen in the setting of suspected endocarditis or critical illness
2. For Listeria monocytogenes: 2 g every 4 hours for 14-21 days; use in combination with gentamicin for nonpregnant patients
Endocarditis, treatment:
1. For Enterococcus faecalis, native or prosthetic valve: 2 g every 4 hours as part of an appropriate combination regimen (eg, with ceftriaxone or gentamicin); duration is usually 4-6 weeks
2. For Viridans group streptococci and Streptococcus gallolyticus: 2 g every 4 hours; in combination with gentamicin if relatively penicillin-resistant
Meningitis, bacterial:
As a component of empiric therapy (community-acquired infections in immunocompetent patients >50 years of age and immunocompromised patients) or pathogen-directed therapy: 2 g every 4 hours for 7-21 days
Urinary tract infections:
Acute pyelonephritis or other complicated urinary tract infection due to Enterococcus spp. (off label): 1 to 2 g every 4 to 6 hours; can give with an aminoglycoside for critical illness

General dosing:
1. 50 to 200 mg/kg/day divided every 6 hours; maximum daily dose: 8 g/day
2. Higher doses (300 to 400 mg/kg/day; maximum daily dose: 12 g/day) are recommended for some infections
Community-acquired pneumonia (CAP):
1. Empiric treatment or S. pneumoniae (MICs for penicillin ≤2 mcg/mL) or H. influenzae (beta-lactamase negative) in fully immunized patients: 150 to 200 mg/kg/day divided every 6 hours
2. Group A Streptococcus: 200 mg/kg/day divided every 6 hours
3. S. pneumoniae (MICs for penicillin ≤4 mcg/mL): 300 to 400 mg/kg/day divided every 6 hours
4. May consider addition of vancomycin or clindamycin if community-acquired MRSA suspected
Endocarditis, treatment:
200 to 300 mg/kg/day divided every 4 to 6 hours; maximum 12 g/day; use in combination with other antibiotics for at least 4 weeks
Intra-abdominal infection, complicated:
200 mg/kg/day divided every 6 hours; maximum 2,000 mg
Meningitis, bacterial:
300 to 400 mg/kg/day divided every 4 to 6 hours; maximum 12 g/day
Surgical prophylaxis:
50 mg/kg within 60 minutes prior to surgical incision; may repeat in 2 hours if lengthy procedure or excessive blood loss; maximum 2,000 mg/dose

1. CrCl 10 to 50 mL/min: change interval to every 6 to 12 hours
2. CrCl <10 mL/min: change interval to every 12 to 16 hours.

There are no dosage adjustments provided in the manufacturer's labeling.