Antivirals Flashcards
What is the common mechanism used to treat DNA virus infections?
Drugs that are analogs of ‘essential chemicals,’ i.e. nucleosides and pyrophosphates
How are antivirals for DNA viruses delivered (molecularly)?
As inactive prodrugs that are activated by a viral enzyme
What enzyme present in cells infected by HSV and VZV activates acyclovir to its nucleoside analog active state?
Thymidine kinase
In a patient with unknown (or missed) renal insufficiency, what may happen if they are given acyclovir?
seizures and altered mental status
Ganciclovir is an analog of what nuceotide?
Guanine
Ganciclovir is used for what viral infection? Specifically what is the most common manifestation it is used to treat?
CMV; CMV retinitis in HIV
Which has more adverse effects, acyclovir or ganciclovir?
Gancyclovir: neutropenia, thrombocytopenia, and CNS
What drug is important in the scenario of acyclovir resistant strains as well as in CMV infections? Does it have tox issues?
Foscarnet: some dose dependent renal and CNS tox
When would you use oseltamivir prophylactically? What is a concern in this use?
high risk confined patients and for family members of the ill; neuropsychiatric side effects in already nervous people
What molecular target of oseltamivir is critical for viral shedding?
Neuraminidase
How long after symptoms start can oseltamivir be used?
1-2 days
What 2 drugs act as nucleotide reverse transcriptase inhibitors? What viruses do they affect?
Zidovudine (AZT) for HIV and Lamivudine for HIV and HBV
Which NRTI can be given IV?
Zidovudine (AZT)
Which antiviral inhibits reverse transcriptase from outside the nucleotside binding site? What 2 concerns are given in its use?
Efavirenz (a NNRTI); has resistance concerns and all in its class cause rash
Protease inhibitors: Amprenavir, bocepravir, ritonavir, and telepravir. Which are for HCV and which for HIV?
HIV: amprenavir and ritonavir
HCV: bocepravir and telepravir
What 2 drugs/classes would you use in resistant strains of HIV? Which additional drug has a mechanism involving CD4/CCR5, and what microbes may have increased virulence in this setting?
enFUrvatide - fusion inhibitor
ralTEGravir - integrase inhibitor
mareviroc - TB, fungi susceptibility
What are the components of HAART? Why combo therapy?
2 NRTIs, 1 NNRTI, and 1 protease inhibitor; limits resistance, especially by using 2 NRTIs
An HIV+ patient comes into your office with symptoms classic for Cushing’s syndrome. What drug are they on and what is their problem called?
A protease inhibitor causing Lipodystrophy Syndrome
Why do you examine side effect profiles of NRTIs in HAART if you are going to prescribe them anyways?
to make sure a single organ won’t get too damaged - spread the tox around
