Antivirals Flashcards
what are the antivirals for influenza
neuraminidase inhibitors: Oseltamivir and Zanamivir
M2 inhibitors: Amantadine and Rimantadine
in depth mechanism of neuraminidase inhibitors (name them)
Oseltamivir and Zanamivir
neuraminidase cleaves sialic acid residues from viral and surface proteins of infected cells –> promotes virion release and prevents clumping of newly released virions
the above drugs inhibits this process
which strain of flu do the neuraminidase treat (name them)
Oseltamivir and Zanamivir
Influenza A and B
most common adverse effects of Oseltamivir
nausea, vomiting, diarrhea, abdominal pain, insomnia, vertigo, and neuropsychiatric issues
adverse effects of Zanamivir
it’s inhaled so usually well tolerated
acute bronchospasm in those with breathing difficulties (asthma and COPD)
mechanism of M2 inhibitors (name them)
Amantadine and Rimantadine
inhibits replication of influenza virus by inhibiting M2
what strain of influenza do the M2 inhibitors work on (name them)
Amantadine and Rimantadine
Influenza A because it is the only one that has the M2 protein
adverse effects of M2 inhibitors (name them)
Amantadine and Rimantadine
anxiety, disorientation, headache
neuro effects are less severe and more frequent with rimantadine
which set of anti flu medication would you give to pregnant women
neuraminidase inhibitors
Oseltamivir and Zanamivir
what are the antivirals for hepatitis
Interferon
Ribavirin
Nucleoside/Nucleotide Analogues: Entecavir and Lamivudine
Protease Inhibitors: Boceprevir and Telaprevir
what is the selective antiviral action of IFNalpha due to
activation of host cell ribonuclease that preferentially degrades mRNA
adverse effects of interferons
flu like symptoms, neurological problems, and depression in those with pre-existing mood disorders
what is ribavirin’s antiviral activity reversed by
guanosine
mechanism of ribavirin
inhibitor of influenza RNA polymerase and mRNA guanylyltransferase
two drugs used together for treatment of HCV
Ribavirin and IFNalpha
adverse effects of ribavirin
sudden deterioration of resp function
cardiovascular effects
hemolytic anemia
SEVERE depression, suicidal ideation, relapse of drug abuse
contraindication of ribavirin
Pregnant women and their male partners
Pre-existing Psychiatric Disorders
what are the protease inhibitors used for treatment in hepatitis
Boceprevir and Telaprevir
mechanism of boceprevir
binds reversibly to HCV nonstructural 3 protein thereby inhibiting viral replication
adverse effect of boceprevir
flu like illness
anemia – fatigue
nausea
dysgeusia – distortion of sense of taste
mechanism of telaprevir
same as boceprevir - binds reversibly to HCV nonstructural 3 protein thereby inhibiting viral replication
adverse effects of telaprevir
anemia, leucopenia, neutropenia, rash
Stevens Johnson rash
mechanism of the nucleos(t)ide analogues used for treatment of hepatitis (name them)
Lamivudine and Entecavir
competitive inhibition of HBV DNA polymerase
also have anti HIV properties
mechanism of Lamivudine
cytosine analogue that is phosphorylated to its active 5 triphosphate metabolite before incorporation into viral DNA by HBV polymerase then causes chain termination
mechanism of Entecavir
guanosine analogue inhibits three functions of HBV DNA polymerase:
- priming of the HBV DNA polymerase
- reverse transcription of the negative strand from the pregenomic RNA
- synthesis of positive strand HBV
antiviral drugs for Herpes
Acyclovir Ganciclovir Penciclovir Cidofivir Foscarnet Trifluridine
what is acyclovir used to treat
guanosine analogue used to treat HSV and VZV
mechanism of acyclovir
turned into acyclovir triphosphate by viral thymidine kinase and human enzymes –> competitive substrate for viral DNA polymerase –> incorporated into DNA chain –> terminate DNA replication
how is acyclovir’s bioavailability increased
use of valacyclovir, valyl ester formulation of acyclovir
big adverse effect of acyclovir
nephrotoxicity
what is ganciclovir used to treat
acyclic 2’-deoxyguanosine analogue used in the treatment of CMV herpes
mechanism of ganciclovir
it is triphosphorylated with first phosphate addition by viral UL97-encoded kinase and other two by human cellular enzymes then incorporated onto DNA chain –> termination of DNA replication
what is ganciclovir used to treat
CMV retinitis in AIDs patient
Herpes simplex keratitis
CMV prophylaxis in transplant patient
most common side effect of ganciclovir
reversible bone marrow suppression
mechanism of penciclovir
guanine analogue that gets triphosphorylated then inhibits DNA polymerase activity since it is a competitive inhibitor for deoxyguanosine triphosphate
what does penciclovir treat
HSV-1, HSV-2, and VZV
major clinical indication for cidofovir
CMV retinitis especially those resistant against ganciclovir
mechanism of foscarnet
non nucleoside pyrophosphate analogue that inhibits pyrophosphate binding to DNA polymerase hence suppressing HSV-1, HSV-2, and CMV replication
most common adverse effect of all these antiviral herpes drug
nephrotoxicity
special adverse effect of foscarnet
other than nephrotoxicity, electrolyte imbalance
mechanism of Trifluridine
thymidine analogue that inhibits thymidylate synthetase and incorporates into viral DNA in place of thymidine
use of trifluridine
opthalmic ointment so used for keratoconjunctivitis and recurrent epithelial keratitis caused by herpes
adverse effect of trifluridine
transient irritation of eye
palpebral edema
