Antivirals Flashcards
Acyclovir
Phosphorylated by viral kinase to become inhibitors of viral DNA syn
Facilitated by HSV thymidine kinase
Oral: genital herpes treatment and suppression, adult varicella zoster
IV: herpes simplex encephalitis, neonatal herpes simplex, serious herpes simplex, or varicella zoster
Docosanol
Fusion inhibitor
Prevents entry into cells and subsequent replication
Herpes
Ganciclovir
Inhibitor action against all herpes viruses but esp active against CMV
Inhibits viral DNA syn
Monophosphorylated by viral thymidine kinase in herpes and phosphotransferase in CMV
AE: myelosuppression and neutropenia
Cidofovir
Completely inhibiting DNA syn and incorporating into viral DNA
Phosphorylation is independent of viral enzyme
AE: dose dependent PCT nephrotoxicity
Must be administered with Probencid
Foscarnet
Inhibits DNA and RNA poly and HIV reverse transcriptase without requiring activation by phosphorylation
AE: nephrotoxicity
Osteamivir
Influenza
Competitively and reversibly interacts with active enzyme site to inhibit viral neuraminidase activity resulting in clumpingof newly released virions to e/o and membrane of infected cell
Early administration is crucial and replication peaks at 24-72hr after onset of sx
Adefovir
Chronic Hep B
Competitively inhibits Hep B DNA Poly and reverse transcriptase causes chain termination after incorporation
AE: acute exacerbation of Hep B upon discontinuation
Entecavir
Compitively inhibits Hep B DNA poly from all three functions
AE: exacerbation of Hep B upon discontinuation
Pegylated interferon alpha 2a, and alpha 2b
Use of pegylated interferon has slower clearance, longer half life, steadier concentration (less frequent dosing)
Ribavirin
Toxic
Should not conceive children for 6 months
Healthcare workers may experience AE (ha, conjunctivitis, rhinitis, nausea, rash)
DAAs
HBV reactivation in pts treated with DAAs resulted in serious liver problems or death
Screen all pts for current or prior HBV infection
Monitor for flare ups or reactivation
Contact provider if fatigue, weakness, loss appetite, n/v, yellow eyes/skin, light colored stools
Sofosbuvir
HCV
Chain termination during RNA replication
Administration with amiodarone not recommended due to symptomatic bradycardia and fatal cardiac arrest
Simeprevir
HCV genotype 1 in combo with Peginterferon and ribavirin
Inhibitors and substrates of CYP3A4
CI with strong 3A4 inducers (Rifampin)
Daclastasvir, Ledipasvir, Ombitasvir
NS5A inhibitors
Reduce RNA levels and enhances SVR in combo with Peginterferon and Ribavirin
Dasabuvir
Non nucleoside polymerase inhibitor
Less potent
Primarily an adjunct
