Lange: Antibiotics Flashcards
Penicillin
*Structural analogs of D-Ala-D-Ala* Cocci (both gram + and -) and spirochetes (like syphilis) Binds PBP–>inhibits peptidoglycan synthesis–>decreased peptidoglycan cross-linking in cell wall *SE = hemolytic anemia, allergy* Resistance = beta-lactamases
Ampicillin/Amoxicillin
Penicillinase sensitive: Often add Clavulanic acid or sulbactam “AMinoPenicillins are AMPed up penicillins:” wider spectrum So all cocci, plus gram negative rods and gram positive rods (Listeria) AmOxicillin has > Oral bioavailability than ampicillin Ampicillin/Amoxicillin “HELPSS kill enterococci”: H flu, E coli, *Listeria*, Proteus, Salmonella, Shigella, enterococci
Piperacillin/Ticarcillin
Tx for pseudomonas Given with Tazobactam (beta lactamase inhibitor)
Methicillin/Nafcillin
Penicillinase resistant So MRSA is something that has alterations in the PBPs (doesn’t break methicillin down, just doesn’t let it bind) “Use naf for staph:” Staph aureus that is But can’t use it for MRSA SE = interstitial nephritis
Aztreonam
To treat severe gram negative infections in pts with penicillin allergy Everything else on the card really stems off of that
Imipenem
Broad-spectrum. The usuals + PEAR (Pseudomonas, enterobacter, anaerobes, gram negative rods) SE= seizures Give Cilistatin too! With imipenem, “the kill is lastin’ with cilistatin:” Inhibits renal dihydropeptidase 1–>prevents imipenem breakdown in renal tubules–>longer imipenem duration of action
Cephalosporins
Generation 1–gram + and also PEcK Generation 2–gram + and also HEN PEcKS Generation 3–serious gram negative infections Ceftriaxone–gonorrhea and meningitis Ceftazidime–Pseudomonas Generation 4–Cefepime, both gram + and serious gram negative infections SE = disulfiram-like reaction with EtOH; hypersensitivity rxn (10% of those allergic to penicillin will get this)
Aminoglycosides (-mycins and Amikacin): Gentamicin, Streptomycin, Neomicin, Tobramycin
Binds 30s–>inhibits initiation complex formation–>mRNA misreading–>nonfunctional proteins Use for severe infections with aerobic gram negative rods (like Pseudomonas) (They require O2 uptake to get into cell so don’t work against anaerobes) SE = ATN (esp with cephalosporins); ototoxic (esp with loop diuretics) (Aerobic, ATN”)
Clindamycin
Binds 50s–>inhibits initiation complex formation “Severe anaerobic infections above the diaphragam.” Like infections d/t nl mouth flora Endocarditis prophylaxis before dental procedures as well SE = pseudomembranous colitis
Linezolid
Also inhibits 50s, but txs MRSA and VRE (gram positive infections)
Chloramphenicol
Binds 50s–>*inhibits peptidyl transferase*–>amino acids can’t get added to chain Broad spectrum, but severe SE. Use = alternative tx for bacterial meningitis in pts with penicillin allergy SE = myelosuppression (*aplastic anemia* (dose independent), dose-dependent anemia) Also gray baby syndrome (with vomiting, shock…)
Macrolides (-thromycins)
“MAC Daddy”: MAC tx and other atypical pneumonias, STDs (what MAC Daddy’s get), Diphtheriae Bind 50s–>inhibit translocation For atypical pneumonias (Mycoplasma, Chlamydia, Legionella, MAC) and some STDs (Chlamydia) And for diphtheria Also for Campylobacter when it is fluoroquinolone-resistant SE = GI upset
Tetracycline (-cyclines)
“Lime in a four wheeler” Binds 30s–>blocks aa-tRNA from binding ribosome–>inhibits protein synthesis For Lyme disease, Rickettsia, atypical pneumonias SE = teeth discoloration and bone deformity in children; Fanconi syndrome; Photosensitivity rash Divalent cations (milk, antacids…) prevent its absorption, so don’t take it with those Fecally eliminated (so can use in renally deficient pts)
TMP-SMX
SMX = PABA analog, competitively inhibits dihydropterate synthetase–>decreased THF TMP–inhibits dihydrofolate reductase–>decreased DNA synthesis For Pneumocystis carinii pneumonia, E coli infections mostly “TMP = PCP” SE = Stevens-Johnson syndrome, hemolytic anemia Or in babies–kernicterus (SE = SJ, HaK)
Fluoroquinolones (-floxacins):
Inhibit bacterial DNA topoisomerase 2–>DNA strand breaks–>cell death For gram negative infections and some gram positive infections Mostly for pneumonias, UTIS, gonococcal infections (PUG) SE = tendonitis and tendon rupture in adults And damage growing cartilage (so pregnant women and children should not take them)
