Antibiotics Questions And Answers – Flashcards

- Bactericidal

- Available in combination with TMP

- Spectrum of activity:

Gram (+) ; not Enterococci

Gram (-) ; limited to respiratory pathogens

Poor against atypicals or anaerobes

E.coli, Chlamydia, Nocardia, PCP, MRSA, Simple UTIs 

Toxicity: cross allergenicity, hyperkalemia, bone marrow suppression, Warfarin binding competition

Sulfonamides

Trimethoprim

- Bacteriostatic

- Often used in combination with sulfonamides as TMP-SMX

Spectrum of activity:

Only Staphylococcus and E.coli

Recurrent UTIs, Shigella, Salmonella, PCP, Ocular infections

Toxicity: Bone marrow suppression resulting in megaloblastic anemia, leukopenia, granulocytopenia

Clindamycin

Chloramphenicol

Linezolid

Aminoglycosides

Macrolides

Tetracyclines

Tigecycline

(CCLAMTT)

- Bacteriostatic

- Binds to 50s ribosomal subunit

- Excellent CNS penetration

Spectrum of activity:

Gram (+) ; MRSA and some VRE

Gram (-) ; common respiratory pathogens

Most anaerobes and atypicals

Meningitis (SHiN), Resistant Gram (+)

Toxicity: SEVERE, anemia, Grey Baby syndrome, aplastic anemia

- Bactericidal

- Bind to the 30s ribosomal subunit, misreading of genetic code

- Require OXYGEN for uptake

Spectrum of activity:

Gram (-)

Limited Gram (+) but synergistic when combined with β-lactam

Part of TB therapy

NO ANAEROBIC/ATYPICAL activity

GRAM (-) infections

Used in combination to treat Gram (+)

Toxicity: Nephrotoxicity, Ototoxicity, Teratogen (NOT)

Production of efflux proteins(increased efflux)

Production of ribosomal protection proteins (decreased uptake)

- Bacteriostatic

- Doxycycline can be used in patients with renal failure

- DO NOT take with dairy produces, antacids, vitamins/mineral supplements because they prevent absorption in the gut 

Spectrum of activity:

Gram (+) ; some MRSA

Gram (-) ; common respiratory pathogens

Oral anaerobes and atypicals

Rickettsia, Chlamydia, Syphilis, Borrelia, H.pylori, M.pneumoniae, B.anthracis

Toxicity: Photosensitivity, do not take with chelating agents, GI distress, inhibition of bone growth in children

- Ribosomal 30s subunit inhibition

- Similar to tetracyclines

Spectrum of activity:

Gram (+)

Gram (-)

Anaerobes

SSTIs, Intra-abdominal infections

Toxicity: hyperemesis

- Bacteriostatic

- Binds to 50s ribosomal subunit

Spectrum of activity:

Anaerobes

Gram (+); some MRSA and enterococci

Anaerobes = Bacteroides fragilis, Clostridium perfringens

abscesses, acne, PID

Toxicity: can cause C.diff overgrowth

- Bacteriostatic against Staph, Entero

- Bactericidal against Strep

- Prevents tRNA binding to A site of ribosome

Spectrum of activity:

Gram (+)

Some Gram (-)

Gram (+) and VRE infections

Toxicity: hypertension, serotonin syndrome

- Bacteriostatic

- Binds to 50s ribosomal subunit

Spectrum of activity:

(SHAM)

Strep, Staph, Enterococci

H. pylori

Atypicals and anaerobes

Mycobacteria

Atypical pneumonias (Chlamydia, Legionella, Mycoplasma),

Gram (+) bacteria, Neisseria

Toxicity: GI upset, potency, hepatic clearance, CYP inhibitors, can prolong QTc interval

- 2nd generation macrolide

- Able to bind at more sites than macrolides

- Active against resistant strains

Spectrum of activity:

Respiratory tract infections

Atypical bacteria

Atypical bacteria, Macrolide resistant strains

Toxicity: highly toxic, same as macrolides

Penicillins

Cephalosporins

Carbapenems

Monobactams

- Bactericidal

- No Atypical Activity

- Inactivation of degrading enzymes (Penicillin-resistant)

- Alterations in PBP enzyme targets (MRSA)

- Well-tolerated

- May need dose reductions due to renal elimination

(exc. Nafcillin, Oxacillin)

- Beta-lactam

- Method of resistance is the production of Beta-Lactamases

Spectrum of activity:

Gram (+) aerobes ; Strep and Entero

Treponema pallidium

Strep and Syphilis, Meningitis, Endocarditis

- Combined with Beta-Lactamase inhibitors, they become more effective

Spectrum of activity:

Gram (+) ; Strep, Enterococci

Limited Gram (-)

Combined: Improved Gram (+), more Gram (-) and some anaerobic activity

SSTIs, Otitis, Lyme disease (2nd line tx)

Spectrum of Activity:

Limited to only Staph and Streptococci

Osteomyelitis, SSTIs

Toxicity: Some hepatic elimination, mild elevations in liver function enzymes

- Less Gram (+) activity

Spectrum of activity:

Gram (-)

Anaerobes

Addition of the beta-lactamase inhibitor improves activity

Broad-spectrum empiris or targeted therapy of nosocomial infections

ALL cephalosporins have NO activity against enterococci

MOST cephalosporins have NO activity against anaerobes

MOST need to have doses reduced due to renal metabolism

Beta-lactam rash considerations

Spectrum of activity:

Gram (+) ; no enterococci or MRSA

SSTIs, Tonsilitis, UTIs

Spectrum of activity:

Gram (+)

Some beta-lactamase Gram (-)

UTIs, sinusitis, Lyme Disease (2nd line tx)

Spectrum of activity:

Gram (-) ; except Pseudomonas

Ceftazidime has Pseudomonal activity

less Gram (+) activity

All of the activity of other cephalosporins

+

Meningitis, UTIs, chronic Lyme disease