Antibiotics


Bugs

Gram (+) . Gram (-)
Cocci Rods (bacilli) Branching filaments Comma Shaped Diplococci "Coccoid"
Rod
Rods
Clusters: (Staph)
S. Aureus
S. Epidermidis
S. Saprophyticus

Chains: (Strep)
S. Pneumoniae
S. Viridans
S. Pyogenes
S. Agalactiae (GBS)
S. Bovis
E. faecialis.
 

Clostridium (anaerobe)

Corynebacterium
Listeria

Bacillus (aerobe)

Mycobaterium (acid-fast)
Anaerobic:
Actinomyces
Nocardia(acid-fast)
C. Jejuni
V.Cholerae
N. Meningitidis
N. Gonorrhea
Haemophilus Influenzae

Bartonella Pretussis

Pasturella
Brucella
Klebsiella
E.coli
Enterobacter
Citerobacter
Serratia
Shigella
Salmonella
Proteus
Pseudomonas
H. Pylori

 

MORPHOLOGY Gram-Positive examples Gram-Negative examples
Circular (coccus) Staphylococcus
Streptococcus
Neisseria
Rod (bacillus) Clostridium
Corynebacterium
Bacillus
Listeria
Mycobacterium (acid fast)
Gardnerella (gram variable)
Enterics:
ƒƒ E. coli
ƒƒ Shigella
ƒƒ Salmonella
ƒƒ Yersinia
ƒƒ Klebsiella
ƒƒ Proteus
ƒƒ Enterobacter
ƒƒ Serratia
ƒƒ Vibrio
ƒƒ Campylobacter
ƒƒ Helicobacter
ƒƒ Pseudomonas
ƒƒ Bacteroides
Respiratory:
ƒƒ Haemophilus (pleomorphic)
ƒƒ Legionella (silver)
ƒƒ Bordetella
Zoonotic:
ƒƒ Francisella
ƒƒ Brucella
ƒƒ Pasteurella
ƒƒ Bartonella
Branching filamentous Actinomyces
Nocardia (weakly acid fast)
 
Pleomorphic   Rickettsiae (Giemsa)
Chlamydiae (Giemsa)
Spiral   Spirochetes:
ƒƒ Borrelia (Giemsa)
ƒƒ Leptospira
ƒƒ Treponema
No cell wall Mycoplasma (does not Gram stain)  


Special groups
Alcoholic/IV drug user S. pneumoniae, Klebsiella, Staphylococcus
Aspiration Anaerobes
Atypical Mycoplasma, Legionella, Chlamydia
Cystic fibrosis Pseudomonas, S. aureus, S. pneumoniae
Immunocompromised Staphylococcus, enteric gram-negative rods, fungi, viruses, P. jirovecii (with HIV)
Nosocomial (hospital acquired) Staphylococcus, Pseudomonas, other enteric gram-negative rods
Postviral Staphylococcus, H. influenzae, S. pneumoniae
 

Normal flora: Dominant

Location Microorganism
Skin S. epidermidis
Nose S. epidermidis; colonized by S. aureus
Oropharynx Viridans group streptococci
Dental plaque S. mutans
Colon B. fragilis > E. coli
Vagina Lactobacillus, colonized by E. coli and group B strep
Neonates delivered by C-section have no flora but are rapidly colonized after birth
 

ABX Overview

 
G(+) cocci
(staph/strep)
G(-) Rods
Enterobacteriae
Anti-Pseudo Anaerobes Doxy Bactrim, G(-) Buggs MRSA
Penicilin, Amoxil
Ox, Clox, Diclox, Naf

1st Gen Ceph:
     Keflex
     Ancef
2nd Gen Ceph:
     Cefoxitin
     Cefoteran
     Cefuroxime(CNS)

Macrolides
Clindamycin

PNC Allergic:

 Vancomycin [MRSA, enterococci, and
Clostridium difficile]
Aminoglycoside
3rd Gen Ceph:
   Rocephin
   Ceftazidime
   Cefixime
4th Gen Ceph:
  CefEPIME

PNC Allergic:
Aztreonam
[G (-) rods only - no activity against G (+) or anaerobes]


 

Ticarcillin
Carbicillin
Pipercillin
Azeocillin
Mezocillin
Aminoglycosides
3rd Gen Ceph:
  Ceftazidime
4th Gen Ceph:
  CefEPIME

Merrem
Zosyn (piperacillin/tazobactam)
Doxy
Bactrim DS

PNC Allergic:

 Aztreonam
[G (-) rods only - no activity against G (+) or anaerobes]
Metro (GI)
Clinda (Oral/Skin)

Merrem (=Metro)

Unasyn (Ampicillin/Sublactam)
Zosyn (piperacillin/tazobactam)
Timentin (ticarcillin/clavulanate)
Augmentin (Amoxicillin/clavulanate)





 
Vibrio
Acne
Chlamydia
Coxiella
Ureoplasma
Mycoplasma Pneum
Tularemia
H Pylori
Borrelia (Lyme)
Rickettsia
Acute Cystitis
Recurrent UTI
Pneumocystis Jeravici
Toxoplasmosis
Salmonella
MRSA
Topical:
- Mupirocin + Chlorhexidine

PO:
- Bactrim
- Doxycycline
- Clindamycin
- Linezolid

IV:
- Vancomycin
- Daptomycin
- Linezolid
- Tigecycline
- Telavancin
- Synercid
Fluroquinolones Fluroquinolones Fluroquinolones Fluroquinolones
Fluroquinolones
(+) S. Aureus
(-) S.Pneumo
(+) Pseudomonas
 

(+) S.Aureus
(+) S.Pneumo

(+) Pseudomonas
(+)
Atypical (Mycoplasma, Legionella, Chlamydia)

Cipro
Floxin
Norfloxacin
    
Levaquin (Levo)
Avelox (Moxi)
Zagam (Saprfloxacin)
Tequin (gatifloxacin) 
(+) = Covers, (-) = Does not cover

 


Penicillins

  Penicillinin Cephalosporin
  Natural PCN Penicillinase Resistant Antistaph. Amino-penicillin Anti-peudomona PCN +
β-lactamase inhibitor
1st GEN 2nd GEN 3rd GEN 4th GEN 5th GEN
Examples PEN G
PEN V
Cloxacillin
Dicloxacillin
Oxacillin
Methicillin
Nafcillin
Ampicillin
Amoxicillin
Ticarcillin
Carbenicillin
Pipercillin
Meziocillin
Azeocillin
Amoxicillin+
Clavulanate
(Augmentin)

Ampicillin+
Sulbactam
(Unasyn)

Ticarcillin+
Clavulanate
(Timentin)

Pipercillin+
Tazobactam
(Zosyn)
Cephalothin
Cephapirin
Cefazolin
Cephalexin
Cephradine
Cefamandol
Cefuroxime
Cefonicid
Ceforanide
Cefoxitin
Cefotaxime
Ceftriaxone
Cefoperazone
Ceftazidime
Cefixime
Cefepime
Cefpirome
Ceftaroline
Spectrum Of Activity Bactericidal for G+ cocci, G+ rods, G- cocci, & spirochetes.
S. pneumoniae
S. pyogenes,
Actinomyces.
N. meningitidis
T. pallidum.

 
S. aureus G+/G-

Haemophilus
influenzae,
E. coli,
Listeria monocytogenes
Proteus mirabilis, Salmonella, Shigella,
enterococci.
Majority G-

Pseudomonas spp. &
G- rods
G+/G- G+ +++
G-  ++

G+ cocci Proteus mirabilis,
E. coli,
Klebsiella pneumoniae.
G+ ++
G-  +++

H.influenzae
Enterobacter
aerogenes
N
eisseria spp.
Proteus mirabilis
E. coli
Klebsiella pneumoniae
Serratia
marcescens
G+ +
G- ++++
 
G+ +
G- ++++
Broad G+ & G- organism coverage, including MRSA
Does not cover Pseudomonas.
Indications -Infection cause by S.Pyogenses & their consequence  Tonsillapharyngitis
- Scarlet Fever
-Erysipelas
-Infection caused by S.Pneumonia
-Community acquired Pneumoniae
-Meningitis
-Sepsis
-Prophylaxis of pneumococcal infections after splenectomy
-Upper & Lower respiratory system
-UTI
-Meningitis
-Endocarditis
Monotherapy of infectious disease Activated by plasmid mediated penicillinase Pre-op

S.aureus infection

Abdominal & Pelvic inf.

H.influenza

Pneumoniae (lung inf.)
 
Anaerobesbes

Ceftriaxone:
meningitis & gonorrhea.

Ceftazidime:
Pseudomonas

Nosocomial inf.

Strep Pneumoniae resistant to penicillin
Pseudom. inf. resistant to 3rd GEN
 
 

Cephalosporins

Drugs Gen. Spect. Emperic $
PO:
Keflex (Cephalexin)
1st G(+): +++
MRSA:  NO
G(-): +, E.coli
Anaerobes: Not much
Atrypial: NO
- Skin, Soft tissue
- UTI
-Pharyngitis
- NO - ears, belly.
$
IV:
Ancef (Cefazolin)
 
PO:
Cefzil (Cefprozil)
 

 

2nd

Respiratory:
G(+): +++, MRSA: NO
G(-): ++
Anaerobes: Not much
Atypicals: NO
  $$$$$$$
IV:
Mefoxin (Cefoxitin)
Surgery:
G(+): ++
G(-): ++
Anaerobes: ++++
Atypical: NO
  $$
PO:
Suprax (Cefixime)
3rd Urinary:
G(+): ++
G(-): ++
Atypical: NO
   
PO:
Vantin (Cefpodoxime)

Omnicef (Cefdinir)


G(+): +
G(-): +++
Anaerobes: +++
   
IV:
Rocephin (Ceftriaxone)

Claforan (Cefotaxime)
   
IV:
Cefepime
 
4th G(+): +++
G(-): ++
Pseudomonas
Comp. UTI
Pyelonephritis
Pneumonia.

Febrile Neutropenia (2g IV q8h x10 d or till resolution)

Skin/soft tissue

 
IV
ceftaroline
(Teflaro)
5th broad G(+) & G(-) Coverage including MRSA;
Does not cover Pseudomonas
CAP
Skin infections.
 

Carbapenems

Imipenem, meropenem, ertapenem, doripenem
 
MECHANISM
  • 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.
CLINICAL USE
  • Gram-positive cocci
  • Gram-negative rods
  • Anaerobes.
  • Wide spectrum, but significant side effects limit use to life-threatening infections or after other drugs have failed.
  • Meropenem has a  risk of seizures and is stable to dehydropeptidase I.
TOXICITY
  • GI distress, skin rash, and CNS toxicity (seizures) at high plasma levels.
 

Vancomycin

MECHANISM
  • Inhibits cell wall peptidoglycan formation by binding D-ala D-ala portion of cell wall precursors.
  • Bactericid
CLINICAL USE
  • Gram positive only — serious, multidrug-resistant organisms, including MRSA, enterococci, and Clostridium difficile (oral dose for pseudomembranous colitis).
TOXICITY
  • Well tolerated in general — but NOT trouble free.
  • Nephrotoxicity, Ototoxicity, Thrombophlebitis, diffuse flushing — red man syndrome (can largely prevent by pretreatment with antihistamines and slow infusion rate).

Aminoglycosides

  • Gentamicin, Neomycin, Amikacin, Tobramycin, Streptomycin
MECHANISM
  • Bactericidal; inhibit formation of initiation complex and cause misreading of mRNA.
  • Also block translocation.
  • Require O2 for uptake; therefore ineffective against anaerobes
CLINICAL USE
  • Severe gram-negative rod infections.
  • Synergistic with β-lactam antibiotics.
  • Neomycin for bowel surgery
TOXICITY
  • Nephrotoxicity (especially when used with cephalosporins),
  • Neuromuscular blockade
  • Ototoxicity (especially when used with loop diuretics).
  • Teratogen
 

Clindamycin

MECHANISM
  • Blocks peptide transfer (translocation) at 50S ribosomal subunit.
  • Bacteriostatic
CLINICAL USE
  • Anaerobic infections (e.g., Bacteroides spp., Clostridium perfringens) in aspiration pneumonia, lung abscesses, and oral infections.
  • Also effective against invasive Group A streptococcal (GAS) infection.
  • Treats anaerobes above the diaphragm vs. metronidazole (anaerobic infections below diaphragm).
TOXICITY
  • Pseudomembranous colitis (C. difficil overgrowth), fever, diarrhea

Fluoroquinolones

  • Ciprofloxacin:
    • remains the most potent marketed fluoroquinolone against gram-negative bacteria
  • Norfloxacin
  • Ofloxacin,
  • Sparfloxacin
  • Levofloxacin
  • Moxifloxacin:
    • Of the available quinolones, only moxifloxacin has sufficient activity against anaerobic bacteria for potential clinical applicability.
    • In a double-blind, randomized trial of patients with complicated intraabdominal infections, moxifloxacin was compared to piperacillin-tazobactam or amoxicillin-clavulanate.
    • Less active than ciprofloxacin against P. aeruginosa, Providencia spp, Proteus spp, and Serratia marcescens
  • Gemifloxacin,
  • Enoxacin (fluoroquinolones),
  • Nalidixic acid (a quinolone).
MECHANISM
  • Inhibit DNA gyrase (topoisomerase II) and topoisomerase IV.
  • Bactericidal.
  • Must not be taken with antacids
CLINICAL USE
  • Gram-negative rods of urinary and GI tracts (including Pseudomonas)
  • Neisseria,
  • Some Gram-positive organisms.
  • Respiratory pathogens — All of the newer quinolones, as well as ciprofloxacin and ofloxacin, are highly active against H. influenzae and M. catarrhalis. However, levofloxacin and moxifloxacin exhibit increased potency relative to ciprofloxacin and ofloxacin against Streptococcus pneumoniae

 

(+) = Covers, (-) = Does not cover
(+) S. Aureus, (-) S.Pneumo, (+) Pseudomonas:  (+)S.Aureus, (+)S.Pneumo, (+)  Pseudomonas, (+) Atypical:
Cipro
Floxin
Norfloxacin

    
Levaquin (Leva)
Avelox (Moxi)
Zagam (Saprfloxacin)
Tequin (gatifloxacin) 
TOXICITY
  • GI upset, superinfections, skin rashes, headache, dizziness.
  • Less commonly, can cause tendonitis, tendon rupture, leg cramps, and myalgias.
  • Contraindicated in pregnant women, nursing mothers, and children under 18 years old due to possible damage to cartilage.
  • Some may cause prolonged QT interval.
  • May cause tendon rupture in people > 60 years old and in patients taking prednisone

Macrolides

  • Azithromycin, clarithromycin, erythromycin
MECHANISM
  • Inhibit protein synthesis by blocking translocation (“macroslides”); bind to the 23S rRNA of the 50S ribosomal subunit. Bacteriostatic
CLINICAL USE
  • Atypical pneumonias (Mycoplasma, Chlamydia, Legionella),
  • STDs (for Chlamydia)
  • Gram positive cocci (streptococcal infections in patients allergic to penicillin).
TOXICITY
  • MACRO: Gastrointestinal Motility issues, Arrhythmia caused by prolonged QT, acute Cholestatic hepatitis, Rash, eOsinophilia.
  • Increases serum concentration of theophyllines, oral anticoagulants.

Metronidazole (Flagyl)

MECHANISM
  • Forms free radical toxic metabolites in the bacterial cell that damage DNA.
  • Bactericidal, antiprotozoal
CLINICAL USE
  • Treats Giardia, Entamoeba, Trichomonas, Gardnerella vaginalis, Anaerobes (Bacteroides, C. difficile).
  • Used with a proton pump inhibitor and clarithromycin for “triple therapy” against H. Pylori.
GET GAP on the Metro with metronidazole!

Treats anaerobic infection below the diaphragm vs. clindamycin (anaerobic infections above diaphragm).
TOXICITY
  • Disulfiram-like reaction (severe flushing, tachycardia, hypotension) with alcohol; headache, metallic taste.

Sulfonamides

  • Famethoxazole (SMX), sulfisoxazole, sulfadiazine.
MECHANISM
  • Inhibit folate synthesis.
  • Para-aminobenzoic acid (PABA) antimetabolites inhibit dihydropteroate synthase.
  • Bacteriostatic
CLINICAL USE
  • Gram-positive
  • Gram-negative
  • Nocardia
  • Chlamydia.
  • Triple sulfas or SMX for simple UTI
TOXICITY
  • Hypersensitivity reactions, hemolysis if G6PD deficient, nephrotoxicity (tubulointerstitial nephritis), photosensitivity, kernicterus in infants.
  • Displace other drugs from albumin (e.g., warfarin).

Tetracyclines

  • Tetracycline, doxycycline, minocycline.
MECHANISM
  • Bacteriostatic; bind to 30S and prevent attachment of aminoacyl-tRNA; limited CNS penetration.
  • Doxycycline is fecally eliminated and can be used in patients with renal failure.
  • Do not take with milk (Ca2+), antacids (Ca2+ or Mg2+), or iron-containing preparations because divalent cations inhibit its absorption in the gut.
CLINICAL USE
  • Borrelia burgdorferi, M. pneumoniae.
  • Drug’s ability to accumulate intracellularly makes it very effective against Rickettsia and Chlamydia.
  • Also used to treat acne
Vaccum THe Bed Room
Vibrio
Acne
Chlamydia
Coxiella
Ureoplasma
Mycoplasma Pneum
Tularemia
H Pylori
Borrelia (Lyme)
Rickettsia
TOXICITY
  • GI distress, discoloration of teeth and inhibition of bone growth in children, photosensitivity.
  • Contraindicated in pregnancy
 

Trimethoprim

MECHANISM
  • Inhibits bacterial dihydrofolate reductase.
  • Bacteriostatic
CLINICAL USE
  • Used in combination with sulfonamides (trimethoprim-sulfamethoxazole [TMPSMX]), causing sequential block of folate synthesis.
  • Combination used for UTIs, Shigella, Salmonella, Pneumocystis jirovecii pneumonia treatment and prophylaxis, toxoplasmosis prophylaxis
TOXICITY
  • Megaloblastic anemia, leukopenia, granulocytopenia.
  • (May alleviate with supplemental folinic acid).
  • TMP: Treats Marrow Poorly.