Mahfouz Content

Antifungals, Non-Retroviral Antivirals

Herpes is a ____ virus sensitive to _____

dsDNA virus sensitive to DNA polymerase inhibitors

What effect does PEGylation have on interferons and why?

Prolongs duration of action and increases plasma concentration due to a large molecular weight

What is Docosanol and its mechanism of action?

saturated 22-carbon aliphatic alcohol; blocks viral entry and replication

What are common side effects of telbivudine?

myopathy and peripheral neuropathy

also GIT disturbances, rash, fatigue

Nucleoside analogues must be activated by _____ to perform what mechanism of action?

phosphorylation (kinases must be functional); inhibit DNA polymerase by chain termination

What are the nucleoside analogues?

acyclovir, valacyclovir, penciclovir, famciclovir

What are the non-nucleoside analogues?

Foscarnet and docosanol

“previr” indicates _____

serine protease inhibitors

“asvir” indicates _______

replicase inhibitors

“buvir” indicates ______

RNA-dependent RNA polymerase inhibitors

What does the flu virus require to detach?

neuraminidase (N) enzyme on the viral coat D

Drugs that block viral DNA/RNA polymerase block what process?

replication

Azole antifungals require what to be active?

acidic pH (inactivated by antacids/PPIs)

What is flucytosine’s mechanism of action?

interferes with nucleic acid (DNA/RNA) biosynthesis and protein synthesis by inhibiting fungal thymidylate synthase and RNA polymerase

What do allylamines target?

squalene epoxidase

What do azoles target?

14 alpha demethylase

What do morpholines target?

delta 14 reductase

What do polyenes target?

ergosterol

What does amorolfine target?

delta 87 isomerase

What are the side effects of amphotericin B and how can this be avoided?

nephrotoxicity due to cholesterol binding; use lipid formulation

What structures form chelation complexes?

Triazole (3N) and imidazole (2N) rings

What do “azole” antifungals act on and what can be used if this is a concern?

CYP enzymes; echinocandins or Naftifine can be used

What azole is independent of pH?

fluconazole

True or false: polyenes and echinocandins are given orally

False, they are given via IV

True or False: morpholines are given topically

True

What do echinocandins interact with?

fungal cell wall biosynthesis via beta D glucan polymers

Yeasts are round, _____, and ______

unicellular; invasive

Molds are filaments, _____ , and ______

multicellular; non-invasive