Antibiotics Flashcards
Cephalosporin
Beta Lactation antibiotics that are derived from acrimonious fungus
MOA cephalosporins
Inhibit bacteria wall synthesis
Bactericidal
Are cephalosporin penicillinase resistant
Yup
Not susceptible to penicillinases
Each new generation of cephalosporin has greater gram _ properties
Negative
Side effects cephalosporin
Hypersensitivity reactions vitamin k defiency
Disulfiram like reaction with alcohol
Increased nephrotoxicity of aminoglycosides
Hypersensitivity cephalosporin
Same with penicillin
Careful giving to people with penicillin allergies
Rashes, hives, itchy eyes, swollen tongue
Cephalosporin vitamin k
Cephalosporin activates vitamin k, causing defiency
Alcohol and cephalosporin
Disulfiram like reaction-flushing, fast heartbeat, nausea, thirst, chest pain, vertigo, low bp
Occurs as a result of accumulation of acetaldehyde due to inhibition of acetaldehyde dehydrogenase
Increased nephrotoxicity of aminoglycosides with cephalosporin
Demonstrate synergistic nephrotoxicity interaction when used in combination
1st generation cephalosporin
Beta Lactation antibiotics that are derived from acrimonious fungus. Inhibit bacterial cell walls ynthesis. Not susceptible to peniciliinases.
Not strong gram -
Examples of first generation cephalosporin
Cefazolin and cephalexin
What are 1st gen cephalosporin effective against
Proteus mirabilis, E. coli, klebsiella pneumonia and gram positive cocci
Cefazolin
Intramuscular
Gram + bacterial infections of the skin but more severe infections involving bon,e lungs, GI and urinary tract. Also pre operative prophylaxis
Cephalexin
Orally
Gram positive infections int he middle ear, bone, lungs, and skin. Also endocarditis prophylaxis
Indications for 1st gen cephalosporin
Proteus mirabilis
E. coli
Klebsiella
Gram positive cocci
2nd gen cephalosporin
Cefoxitin, cofactors and cefuroxime
For proteus mirabilis, E. coli, klebsiella, haemophilus influenza, enterobacter, neisseria, serratia marcescens and gram positive cocci
Cefoxitin
Gram negatives, gram positive and even anaerobes.
NOT for active against pseudomonas and enterococci
Cefaclor
For septicemia, pneumonia peritonitis, UTI and biliary tract infections. It is active against both gram positive and gram negative bacteria
Cefuroxime
Unlike other second generations can cross the BBB and is active against haemophilus influenza, neisseria gonorrhea and Lyme disease
Indications for 2nd generation
Proteus mirabilis E. coli Klebsiella Gram positive cocci Haemophilus influenza Enterobacter Neisseria Serratia marcescens
3rd generation cephalosporin
Ceftriaxone, cefotaxime, and ceftazidime
Broad spectrum
Good against gram negative organisms resistant to other beta lactate
Cefotaxime
Respiratory infections, CT, urinary tract, genita tract, meninges, and blood. Can cross the BBB
Most gram negative bacteria (espicially pseudomonas) also gram positive cocci, except enterococcus
Ceftriaxone
Community acquired pneumonia, haemophilus influenza infection, and can be used for bacterial meningitis.
GONORRHEA from dingle muscular injection
Can cross the BBB
Cefdinir
Pneumonia, bronchitis, ear infections, sinusitis, pharyngitis, tonsillitis, skin infections.
Side effects cefdinir
Can bind iron in GI and cause red stool
Diarrhea, vaginal infections, nausea, head ache, abdominal pain
Ceftazimidime
Gram positive and gram negative bacteria. ACTIVE AGAINST PSEUDOMONAS
Whic third generation cephalosporin should i use for pseudomonas
Ceftazidime
Indications for 3rd gen cephalosporin
Serious gram negative infections, which are typically resistant to other beta Lactation antibiotics
4th gen cephalosporins
Cefepime
Broad spectrum of activity and further increased activity against gram negative organisms resistant to other beta lactams
Used for pseudomas a
Cefepime
For moderate-severe hospital acquired infections by multi resistant bacteria such as pseudomonas and can cover resistant strep p as well as enterobacteriaceae
Indications 4th gen cephalosporin
Increased activity against gram positive infections and pseudomas and gram positive infections like staph a…also gram -
5th generation cephalosporin
Broad spectrum
Specifically created for resistant organisms such as MRSA
Indications 5th generation cephalosporin
Resistant bacteria like MRSA
Broad spectrum against gram positive and gram negative
Examples of 5th generation cephalosporin
Ceftobiprole
Ceftaroline
Ceftobiprole
Antipseudomonal (binds strongly to penicillin binding protein 2a)
MRSA, strep p, enterococci, health care associated pneumonia (powerful antipseudomnonal)
MRSA which are less susceptible to daptomycin , vancomycin or linezolid
Ceftaroline
Broad spectrum activity against many gram positive organisms, such as MRSA, MRSE, and VRE.
Not great for gram - bacteria like bacteroides
NO PSEUDOMONAS COVERAGE
Protein synthesis inhibitors
Slows or stops the growth or proliferation of cells by disrupting the generation of new proteins, usually the ribosome level
Protein synthesis inhibitors prok vs euk
Effect only prokaryote 30 50s =70s
Protein synthesis inhibitors of 30s ribosome
Aminoglycosides
Tetracyclines
Protein synthesis inhibitors 50s
Chloramphenicol Clindamycin Erythromycin Linomycin Linezolie
Aminoglycosides
Bactericidal
Inhibit formation of the initiation complex and cause misreading of. MRNA. They require oxygen for uptake and are ineffective against anaerobes and are typically used for severe gram - rod infections
Tetracyclines
Bacteriostatic
Prevent attachment of 30s to aminoacyl-trna
Examples of tetracyclines
Doxyclycline
Demeclocycline
Minocycline
What are tetracyclines used for
Lyme
H pylori
M pneumoniae
Rickettsia and chlamydia
Chloramphenicol
Bacteriostatic inhibits 50s peptidyltransfersase
Why is chloramphenicol rarely used in the US and more in developing countries
Severe toxicities-anemia, plastic anemia and gray baby syndrome
But its cheap
Clindamycin
Bacteriostatic
Blocks peptide bond formation at 50s
What in clindamycin used for
Bacteroides fragility and clostridium perfringens above the diaphragm
Erythromycin
Inhibits protein synthesis by binding to the 23 rRNA and 50s subunit and blocking translocation
What in erythromycin used for
Atypical pneumonia caused by mycoplasma, chlamydia and legionella as well as URI and TDS
Lincomycin
Binds 50s similar structure to macrolides
Why in lincomycin rarely used
Adverse effects and toxicity
Reserved for patients with penicillin allergies and high resistant bacteria
Linezolid
Binds 50s for gram positive infections that are resistant to other antibiotics like strep, vancomycin resistant enterococci, mrsa
Indication for linezolid
Infections of skin, soft tissue and hospital acquired pneumonia
Linezolid (zygote)
Bacteriostatic part of oxazolidinone class inhibit 50s
What is linezolid used for
Gram positive causes of pneumonia and skin infections as well as MRSA and WRE
Why linezolid not commonly used
Expensive, severe adverse effects, hard to obtain
Side effects linezolid
Bone marrow suppression, serotonin syndrome