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Flashcards in Antivirals Deck (16):

zanamivir, oseltamivir

inhibit influenza neuraminidase --> decrease the release of progeny virus
- used for treatment and prevention of influenza A and B


ribavirin mech, use and tox

-inhibits synthesis of guanine nucleotides by competitively inhibiting inosine monophosphate dehydrogenase
- used for RSV, chronic Hep C
- tox: hemolytic anemia, severe teratogen


acyclovir, famciclovir, valacyclovir mech and clinical use

- monophosphorylated by HSV/VZV thymidine kinase and not uninfected cells. guanosine analog, triphosphate formed by cellular enzymes
-preferentially inhibits viral DNA polymerase by chain termination
- used for HSV, VZV, weak activity against EBV
- use famciclovir for herpes zoster


ganciclovir mech and clinical use

- 5' monophosphate formed by a CMV viral kinase
- guanosine analog
- triphosphate formed by cellular kinases, preferentially inhibits viral DNA polymerase
- used for CMV, esp immunocompromised pts
-valgancyclovir has better oral availability


acyclovir, famciclovir, valacyclovir tox and mech of resistance

- tox: obstructive crystalline nephropathy and acute renal failure if not hydrated
- resist: mutated viral thymidine kinase


ganciclovir tox and mech of resistance

- tox: leukopenia, neutropenia, thrombocytopenia, renal tox
- resist: mutated CMV DNA polymerase or lack of viral kinase


foscarnet mech and clinical use

- viral DNA polymerase inhibitor that binds to pyrophosphate binding site of the enzyme. does not require activation by viral kinase
- used in CMV retinitis when ganciclovir fails, or in acyclovir-resistant HSV


foscarnet tox and mech of resistance

- tox: nephrotoxic (can lead to hypocalcemia and hypomag --> seizures)
- resist: mutated DNA polymerase



- preferentially inhibits viral DNA polymerase, does not require phosphorylation
- used in CMV retinitis and acyclovir resistant HSV
- long half life
- tox: nephrotoxic (give probenecid and IV saline)


protease inhibitors

- prevent cleavage of polypeptide products of HIV (will see increased pol mutations with treatment)
- ritonavir is a P450 inhibitor
- all end in navir
- tox: hyperglycemia, GI intolerance, lipodystrophy
- idinavir causes nephropathy and hematuria



- no 3'OH, DNA chain terminators
- zidovudine (formerly AZT) given during pregnancy to decrease fetal transmission
- tox: bone marrow suppression, peripheral neuropathy, lactic acidosis, rash, anemia, pancreatitis (didanosine)


NRTI names

abacavir, didanosine, emtriitabine, lamuvidine, stavudine, tenofovir, zidovudine (formerly AZT)



- bind to reverse trascriptase, but not at nucleoside binding site
- do not require phosphorylation
- rash and hepatotoxicity
- names: efavirenz, necirapine, delaviridine


integrase inhibitors

- raltegravir
- inhibits HIV genome integration into host cell by reversibly inhibiting HIV integrase
- tox: hypercholesterolemia


fusion inhibitors

- enfuvirtide binds gp41, inhibiting viral entry
- maraviroc binds CCR5, inhibiting interaction with gp120
- tox: skin reaction at injection site


interferons mech, use and tox

- glycoproteins usually synthesized by virus-infected cells, wide range of antiviral properties
- alpha used in Hep B/C, Kaposi sarcoma, hairy cell leukemia, condyloma acuminatum, RCC and malignant melanoma
- beta used in MS
- gamma used in chronic granulomatous disease
- tox: neutropenia, myopathy