Antimetabolites, Fluoroquinolones, Anti-TB Agents Flashcards
Name the drug:
Binds to DHPS → prevent production of dihydropteroic acid → decreased production of necessary components of DNA and RNA synthesis
Sulfonamides
Sulfonamides
Bacteriostatic or bactericidal?
Bacteriostatic
Sulfonamides
Spectrum:
Broad: Gm+ and Gm-
Some parasites: plasmodium, toxoplasma gondii
Name the drug:
Do NOT use for Rickettsia. Will actually stimulate growth.
Sulfonamides
Name the drug:
Blocks later step in folic acid synthesis pathway than sulfas
Inhibits bacterial DHFR
Trimethoprim
Trimethoprim
Bacteriostatic or bactericidal?
Bacteriostatic
Sulfonamide often combined with ___ to work synergistically
Trimethoprim
Which of the following is NOT a side effect of Sulfonamides? A. Kernicterus B. GI distress, rash C. Hemolytic anemia D. Anti-folate effect E. Stevens-Johnson Syndrome
D. Anti-folate effect is seen in Trimethoprim
Also bone marrow and liver toxicity (uncommon)
Which TWO are part of the spectrum of Trimethoprim?
A. Pseudomonas
B. Anaerobes (gut microbes)
C. Gm +
D. Atympical bacteria (leginella, mycoplasm)
E. Gm-
C, E
All other are definitely NOT a part of the spectrum
Name 3 ways microbes become resistant to Trimethoprim
Overexpression of DHFR
Express mutant DHFR resistant to Tmp
Increasing, location dependent
Which of the following is NOT a common use of Trimethoprim? A. UTI B. CA-MRSA C. Malaria D. Sinusitis E. Otitis media F. Pneumocystis pneumonia
C. This is use of Sulfonomides. CNS toxoplasmosis is another use of sulfas.
Name the 3 Quinolones
Ciprofloxacin
Levofloxacin
Moxifloxacin
T/F: Quinolones have worse Gm+ coverage than other abx
False. It’s better
Name the drug:
Inhibit bacterial DNA gyrase and topoisomerase –> block DNA unwinding –> irreversible DNA damage/degradation
Quinolones
Quinolone AUC/MIC for immunocompetent pt
25
Quinolone AUC/MIC for immunocompromised pt
100
Administration of Trimethoprim
Oral
Distribution of Trimethoprim
Wide
CNS and prostate
Administration of Quinolone
Oral, IV
Distribution of Quinolone
Wide w/ high bioavailability
Bone and prostate
Bad CSF
Which of the following is NOT a part of Quinolone's spectrum of activity? A. Anaerobes B. complicated Gm- C. Pseudomonas D. Legionella, mycoplasma, chlamydia
A. Anaerobes
Quinolone is excellent against the others
Which of the following is NOT a mechanism of resistance against Quinolones? A. Decreased permeability B. Overexpression of gyrA C. Mutation of gyrase and topoisomerase D. Efflux pump
B. Not overexpression. Mutations in genes gyrA and parC causes high resistance
T/F Quinolones are not well tolerated due to its high toxicity
False. Quinolones are well tolerated.
Name contraindications of Quinolones
Children
Atheletes/old people: Achilles tendon rupture
Pregnancy: cause birth defects and spontaneous abortions
Which of the following is NOT a common use of Quinolones? A. Complicated UTIs B. Otitis media C. Acute bacterial prostatitis D. Pneumonia E. STDs
B. Otitis media is a use of Trimethprim
Majority of use considered inappropriate
Which of the following is NOT a first line drug of tuberculosis? A. Isoniazid B. Rifampin C. Fluconazole D. Ethambutol E. Pyrazinamide F. Streptomycin
C. Fluconazole is an antifungal
Name the drug:
Inhibits mycolic acid synthesis
Isoniazid (INH)
First line TB drug
Name the drug:
Inhibit bacterial RNA polymerase
Rifampin (RMP)
First line TB drug
Name the drug:
Inhibits cell wall glycolipid synthesis
Ethambutol (ETH)
First line TB drug
What is the most effective individual anti-TB agent?
Rifampin
Rifampin
Bactericidal or bacteriostatic?
Bactericidal
Pyrazinamide
Bactericidal or bacteriostatic?
Bactericidal
Ethambutol
Bactericidal or bacteriostatic?
Bacteriostatic
Name the 2 TB drugs that are administered as a prodrug
Isoniazid
Pyrazinamide
Causes red-orange color to bodily fluids
Rifampin
