Flashcards in Infectious Diseases: Antimicrobials Deck (49):
What is the MOA of sulfonamides?
Synergistic inhibition of folate metabolism, resulting in inhibition of purine (DNA/RNA) synthesis
What does Trimethoprim inhibit?
What are sulfonamides a competitive inhibitor of?
What is the spectrum of sulfonamides?
Broad spectrum (Gram + and - especially Nocardia)
In which tissue do sulfonamides have great penetration?
What are the adverse effects of sulfonamides? (5)
1. Immune-mediated thrombocytopenia
3. Bone marrow suppression
What is TMS?
Is TMS bacteriostatic or bactericidal?
What 3 tests would you use to monitor adverse effects associated with sulfonamides?
1. Shirmer tear test
2. Liver panel
Name 4 aminoglycosides...
What is the MOA of aminoglycosides?
Inhibit protein synthesis by binding to 30S ribosomal subunit
Against which class of bacteria do aminoglycosides have excellent activity?
Which class of bacteria have intrinsic resistance to aminoglycosides?
Because aminoglycosides have poor oral absorption, how can you administer them?
SQ, IM, IV
What are the adverse effects of aminoglycosides?
What is the MOA of chloramphenicol?
Inhibition of protein synthesis by binding 50S ribosomal subunit
What is the spectrum of chloramphenicol?
Broad (+/-) and anaerobes
What are the 3 adverse effects associated with chloramphenicol?
1. Irreversible aplastic anemia
2. Reversible bone marrow suppression
3. GI effects
Name 3 tetracyclines....
What is the MOA of the tetracycline?
Inhibition of protein synthesis by binding the 30S ribosomal subunit
What is the spectrum of tetras?
1. Gram +
2. Some gram -
3. Intracellular bacteria
What are the adverse effects associated with tetras?
1. Teeth discoloration (tetracycline specifically)
4. Esophageal strictures
Name a lincosamide...
Name a macrolide...
What is the MOA of the Lincosamides and Macrolides?
Inhibit protein synthesis by binding to 50S ribosomal subunit
Where do Lincosamides achieve high concentrations?
Where do Macrolides achieve high concentrations?
What is the spectrum of lincosamides?
1. Gm +
What are the AE associated with lincosamides?
Esophagitis in cats
What is the spectrum of macrolides?
1. Gm +
2. Some gm -
What is the AE associated with macrolides?
What is the MOA of the azoles?
Interfere with ergosterol synthesis inhibition of 14a-demethylase
Are the azoles fungistatic or fungicidal?
Name 2 classes of azoles...
Name 3 imidazoles...
Name 4 triazoles...
Which has good bioavailability, the imidazoles or the triazoles?
Triazoles (the imidazoles have poor bioavailability and should only be used topically)
What are the 4 adverse effects associated with azoles?
2. Inhibition of mammalian p450
4. Ulcerative lesions in dogs with itraconazole
Which azole is the most hepatotoxic?
What are the 2 MOA of amphotericin B?
1. Causes pores in the cell membrane by binding to sterols
2. Macrophage activation
Is amphotericin B fungistatic or fungicidal?
Fungistatic at low doses
Fungicidal at high doses
What are the adverse effects associated with amphotericin B?
What is the MOA of 5-flucytosine?
Interferes with DNA replication
What is 5-flucytosine?
A fluorinated pyrimidine
What organisms is 5-flucytosine effective against?
What are the adverse effects associated with 5-flucytosine?
1. Cutaneous drug eruption in dogs
How can you prevent resistance to 5-flucytosine?
NEVER USE ALONE: Always combine with another anti-fungal drug.
What is the MOA of terbinafine?
Inhibition of squalene epoxidase --> intracellular accumulation of squalene --> cell lysis