Antivirals Flashcards
(21 cards)
Immunological
Level of Effectiveness: High
Spectrum: Narrow
Duration: Long
Interferon
Level of Effectiveness: Moderate/High
Spectrum: Broad
Duration: Short
Chemical
Level of Effectiveness: Low/Moderate
Spectrum: Narrow
Duration: Short
Acyclovir
Guanosine nucleoside analog. For Herpes, CMV, Epstein-Barr. Metabolized to mono,di,tri-P to decrease Guanosine for DNA, and incorporate chain termination. Abs. Oral, Topical. Dist. to CSF. Renal E. Tx: mild GI upset, headache, renal toxicity
Gancyclovir
Guanosine nucleoside analog. For Herpes, CMV. Abs. Oral. Dist. to CSF. Tx: Bone Marrow, CNS, teratogenic (worse side effects than acyclovir, b/c more incorporated into host DNA)
Iododeoxyuridine
Tymidine analog. For DNA viruses, herpes. Decreases viral DNA synthesis and incorporated into DNA, so it cannot serve as template. Affects mammals too (toxic), limited to topical use.
Vidarabine
Adenosine analog. DNA viruses, sometimes used with acyclovir. Metabolized to tri-P, and competes with adenine to incorporate into DNA - chain termination.
Amantadine
Anti Influenza A - Treat and Prevent (prophylaxis). Inhibits M2, blocking viral uncoating. Abs. Oral. Unclear dist. to CSF. Renal E. Tx: Minor GI, CNS (5-33%): nervous, light headed, difficulty concentrating. NOTE: Widespread resistance, limited use.
Oseltamivir
Anti Influenza A - Treat and Prevent. Inhibits viral neuraminidase (requires confirmational change). Virus accumulates at cell surface - no release. Abs. Oral. Unclear dist. to CSF. Renal E. Tx: Mild GI
Zanamivir
Anti Influenza A and B - Treat and Prevent. Same mech as Oseltamivir, but no conformational change. Abs. Intranasal or dry powder inhalation (NOT GI). Renal E. Tx: Well tolerated, some wheezing/bronchospasm (rare).
Interferons
Protective production in response to viral infection. Blocks penetration, uncoating, RNA/protein synthesis. 2 types: Alpha (used most), Beta (most cells produce), Gamma (stimulate T cells). Abs. IV. For Hep B/C. Tx: Fever, chills, headache, BM suppression, CNS: confusion, behavioral changes.
Lamivudine
Cytidine nucleoside analog. For Hep B. Metabolized to tri-P. Inhibits DNA polymerase and RT (against HIV) - chain termination. Abs. Oral to total body water. Renal E. Tx: Mild liver.
Zidovudine (AZT)
Thymidine Analog. RT inhibitor: Incorporates into DNA - causes premature termination. Abs. Oral. Liver metabolism, Renal E. Tx: Fatigue, nausea, headache, anemia.
Nevirapine
RT Inhibitor: Does not cause premature termination. Abs. Oral. Tx: Rash, fever, fatigue, nausea, liver toxicity. (Effective when there is resistance to AZT).
Efavirenz
RT Inhibitor: Does not cause premature termination. Abs. Oral. Tx: CNS: 50% - impaired concentration, abnormal dreams, headache, dizzyness. 5% - must stop and have rash. (Effective when there is resistance to AZT).
Atazanavir and Indinavir
Protease Inhibitor: Stop cleavage of viral proteins to active enzymes, block viral maturation. Antimetabolite. Inhibits Cytochrome P450 mediated metabolism. (Can inhibit metabolism of many drugs).
Enfuvirtide
Entry Inhibitor: Blocks fusion of virus and host. Binds gp41 on virus. Abs. subQ.
Maraviroc
Entry Inhibitor: Blocks fusion of virus and host. Binds host CCR5. Not effective agains HIV that targets CXCR4. Abs. Oral.
Raltegravir
Integrase Inhibitor: Inhibits integration of RT HIV DNA into Host DNA. Binds HIV integrase and inhibits DNA strand transfer.
Simeprevir (Olysio)
Protease Inhibitor: Prevents viral maturation. Treats Hep C. Used in combo w/ Ribavirin or Interferon. Very Expensive.
Sofosbuvir (Sovaldi)
Nucleotide analong, inhibits viral RNA polymerase. Pro-drug, nucleoside metabolized to tri-P (active form). Treats Hep C. Used in combo w/ Ribavirin or Interferon. Very Expensive.
