C/8. Penicillins Flashcards
Penicillins
MOA
Inhibit cell wall synthesis
Beta-lactam antibiotics bind specific PBP’s in the bacterial wall and inhibit assembly of the peptidoglycan chains, resulting bacterial cell death (bactericidal effect)
Penicillin
Pharmacokinetic/dynamic properties
Orally active(resistant to gastric acid inactivation)
Parenteral formulation (penicillin G, ampicillin, piperacillin, tigarcillin)
Excreted unchanged in the urine
Biliary clearance (nafcillin, oxacillin), enterohepatic cycling (ampicillin)
Short half life, requires multiple dosing 3-4 times daily, or continuous IV infusion
Cross BBB only when meninges are inflamed
Synergistic effect with aminoglycosides
Enhanced if used in combination with beta-lactamase inhibitors (Clavularic acid, sulbactam, tazobactam)
Penicillin
Penicillin G(IV) Penicilling V(Oral)
Narrow-spectrum
Beta-lactamase sensitive
Streptococcal infections(pharyngitis, rheumatic fever, endocarditis)
Gram positive rods (Actinomyces israelii)
Clostridium perfringens
Entercocci
Prophylaxis against group B strp. (S. Agalactiae)
Neisseria meningitis
Hypersensitivity/allergic reaction; fever, urticaria, pruritus, joint swelling, anaphylaxis
Drug induced hemolytic anemia
Intestitial nephritis
Jarisch-Herxheimer reaction
Benzathine penicillin G
Syphilis - IM depot injection (slow release)
Oxacillin
Very narrow spectrum
Beta-lactamase resistant
Staphylococcal infections (skin and soft tissue infections, endocarditis, osteomyelitis)
Interstitial nephritis
Neutropenia
Ampicillin
Ammoxicillin
Broad-spectrum
Beta-lactamase sensitive
Amino-peniciilin
Ampicillin (IV)
against gram - rods E.coli, enterococci L. Monocytogen Anaerobic infection Otitis media and sinusitis caused by H. Influenza, S. Pneumoniae, M. Catarrhalis Pneumonia caused by S. Pneumoniae and H. Influenza Streptococcal pharyngitis H. Pylori eradication Borellia burgdoferi Prophylaxis
Maculopapular skin rash
GI disturbances
Steven-Johnson syndrome
Piperacillin
Extended-spectrum
Beta-lactamase sensitive
Ureido-penicillin
Pseuomonas infection
Sepsis
Commonly used combination preparations
Amoxicillin/Clavularic acid (Augmentin)
Ampicillin/Sulbactam
Piperacillin/Tazobactam