Antibiotics 1 Flashcards
👾=mechanism of action
🤮=side effect
🤷🏻♀️= حجي عن الموضوع
💊💉👉🏿= what drug to use for what
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Gram - bacteria
🔸An inner cell membrane is present (cytoplasmic)
🔸A thin peptidoglycan layer is present (This is much thicker in gram-positive bacteria)
🔸Has outer membrane containing ✨lipopolysaccharides (LPS, which consists of lipid A, core polysaccharide, and O antigen) in its outer leaflet and phospholipids in the inner leaflet
Gram + bacteria
🔸Cytoplasmic lipid membrane
🔸Thick peptidoglycan layer
🔸Teichoic acids and lipoids are present, forming lipoteichoic acids, which serve as chelating agents, and also for certain types of adherence.
🔸Peptidoglycan chains are cross-linked to form rigid cell walls by a bacterial enzyme DD-transpeptidase.
Penicillin resistant??
🔷b lactamase
🔷Dec the permeability of the drug
🔷Alter pbp(penicillin binding protein)
Amoxicillin 🤷🏻♀️
Amoxil if by itself Clavulanic acid (bete lactamase inhibitors)+ amoxicillin (AUGMENTIN)
Penicillin 👾👾
Bind penicillin-binding proteins (transpeptidases). Block transpeptidase cross-linking of peptidoglycan in cell wall.
Activate autolytic enzymes.
Syphilis 💊💊
Give benzathine benzyl penicillin) If
allergy, give erythromycin, tetracycline or Doxycline
Penicillin 🤮🤮
Hypersensitivity reactions, direct Coombs ⊕ hemolytic anemia, drug-induced interstitial nephritis.
penicillinase sensitive penicillins
Amoxicillin, ampicillin; aminopenicillins.
Penicillinase-resistant penicillins
Dicloxacillin, nafcillin, oxacillin.
Penicillinase-resistant penicillins mechanism
Same as penicillin. Narrow spectrum; penicillinase resistant because bulky R group blocks access of β-lactamase to β-lactam ring.
β-lactamase inhibitors
Include Clavulanic acid, Avibactam, Sulbactam, Tazobactam. Often added to penicillin antibiotics to protect the antibiotic from destruction by β-lactamase (penicillinase).
cephalosporins
β-lactam drugs that inhibit cell wall synthesis but are less susceptible to penicillinases. Bactericidal.
bacteria not included by 4 th cephalosporins
rganisms typically not covered by 1st–4th generation cephalosporins are LAME: Listeria, Atypicals (Chlamydia, Mycoplasma), MRSA, and Enterococci.
cephalosporins clinical use
3rd generation (ceftriaxone, cefotaxime, cefpodoxime, ceftazidime)—serious gram ⊝ infections resistant to other β-lactams. Can cross blood-brain barrier. Ceftriaxone—meningitis, gonorrhea, disseminated Lyme disease. Ceftazidime—Pseudomonas.
carbapenems babies
Doripenem, Imipenem, Meropenem, Ertapenem (DIME antibiotics are given when there is a 10/10 [life-threatening] infection
imipenem
Imipenem is a broad-spectrum, β-lactamase– resistant carbapenem. Always administered with cilastatin (inhibitor of renal dehydropeptidase I) to inactivation of drug in renal tubules.
carbapenems ADR
GI distress, rash, and CNS toxicity (seizures) at high plasma levels.
monobactam mech..
Aztreonam
Less susceptible to β-lactamases. Prevents peptidoglycan cross-linking by binding to penicillinbinding protein 3. Synergistic with aminoglycosides. No cross-allergenicity with penicillins.
vancomycin mech..
inhibit the cell wall synthesis
vancomycin use
Gram ⊕ bugs only—serious, multidrug-resistant organisms, including MRSA, S epidermidis, sensitive Enterococcus species, and Clostridium difficile (oral dose for pseudomembranous colitis).
vancomycin ADR
oto and nephrototic and thrombophlebitis, diffuse flushing red man syndrom
Amoxicillin, ampicillin; aminopenicillins
🤮
Hypersensitivity reactions, rash, pseudomembranous colitis.
Dicloxacillin, nafcillin, oxacillin
ADR.
Hypersensitivity reactions, interstitial nephritis
