Medical Pharmacology: Antiviral Drug Practice Questions

Famciclovir (Famvir):
1. Is classified as a "prodrug."
2. Is a precursor to penciclovir (Denavir)
3. Both
4. Neither
Famciclovir (Famvir):
1. Diacetyl ester of 6-deoxypenciclovir, and acyclic guanosine analog.
2. Famciclovir by deacetylation and hepatic first-pass oxidation reactions is converted to penciclovir.
3. Both
4. Neither
Penciclovir antiviral (in vitro) activity:
1. HSV-1 and HSV-2
2. Varicella zoster virus (VSV)
3. Epstein-Barr virus (EBV)
4. A & B
5. B & C
6. A, B & C
Penciclovir (Denavir): antiviral activity
1. Requires virus-specific thymidine kinase found in virally infected cells. This kinase catalyzes drug phosphorylation.
2. Penciclovir inhibits viral DNA polymerase by competitive inhibition with a resulting blockade of DNA synthesis.
3. Penciclovir, like acyclovir causes DNA chain termination.
4. A & B
5. B & C
6. A & C
7. A, B & C
Penciclovir triphosphate: Higher intracellular concentration when compared with acyclovir triphosphate.
1. True
2. False
Penciclovir: topical use
1. Reduces duration of recurrent herpes labialis by about 17 hours, providing the drug is applied both very early and with appropriate application frequency.
2. Generally infrequent adverse effects are noted besides application site reactions (1%).
3. Both
4. Neither
Penciclovir (Denavir) pharmacokinetics:
1. Bioavailability: about 70% (following oral famciclovir administration)
2. Penciclovir triphosphate half-life: ranges from 7 to about 20 hours.
3. Both
4. Neither
Penciclovir clincial indication: treatment of recurrent herpes of labialis (cold sores) in both children 12 years or older and in adults.
1. True
2. Files
Systemic drug-drug interactions involving penciclovir are considered improbable due to very limited systemic drug absorption.
1. True
2. False
Due to an apparent lack of systemic drug absorption following topical use, maternal use is unlikely to result in fetal exposure to penciclovir.
1. True
2. False