Pharm - antiviral drugs Flashcards
Acyclovir area of use?
Viruses that have the Thymidine kinase enzyme to activate the drug. These viruses are Herpe simplex 1 and 2 and Varicella Zoster.
These viruses have a dormant part of their life cycle which means you do not cure the infections due to non-replicant viruses.
Mechanism of action of “-ovirs”?
prodrug that is activated by host kinases. The active metabolite lach 3’ -OH which will terminate the DNA chain transcription = chain terminators.
Foscarnet mechanism of action?
Inhibits DNA and RNA polymerases. Areas of use are identical to those of ganciclovir.
Foscarnet side effects?
renal toxicity - acute tubular necrosis
HAART =
Highly Active Anti Retroviral Therapy
Treatment of HIV general picture?
Reverse Transcriptase inhibitors
efavirenze and sleep`?
can produce dysphoric dreams, commonly known as NIGHTMARES!!
Zidovudine(ZDV) and Azidothymine(AZT) mechanism of action?
Compete with natural nucleotides and can also be incorporated into viral DNA to cause chain termination ===> chain terminator
Other NRTIs mechanism of action?
Same as ZDV except the active metabolite express different nucleotide that inhibit RT.
ide effects of AZT?
Hematotoxicity(major and dose-limiting)
“-udine”“-tabine”“-vudine” indicates ………
“-udine”“-tabine”“-vudine” indicates antiretroviral
HIV: Protease inhibitors mechanism of action?
Aspratate protease(pol) cleaves precursor polypeptides in HIV that buds to form the proteins of the mature virus core.
This enzyme, aspartate protease, contains dipeptide structures which the PIs can bind to, thereby inhibiting the enzyme.
Resistance occurs via specific point mutations in pol gene
indinavir and ritonavir are ………..
indinavir and ritonavir are rotease inhibitors
side effects of PIs?
crystaluria(keep patient hydrated), major drug interactions, syndrome of disordered lipid and carbohydrate metabolism
Enfuvirtide mechanism of action?
binds gp41 and inhibits fusion of HIV-1 to CD4+ cells
Maraviroc mechanism of action?
blocks CCR5 protein on T-cell surgace to prevent viral entry
Amantadine mechanism of action?
blocks attachement, penetration and uncoating of influenza A virus
Zanamivir and Oseltamivir mechanism of action?
inhibit neuraminidases of influenza A and B; decrease the likelyhood that the virus will penetrate uninfected cells.
prophylaxis mainly
Acyclovir moa?
Purine analogue that needs viral Thymidine kinase to be converted to monophosphate –> inhibits DNA polymerase
Valacyclovir target organisms?
- CMV in immunocompromised
- EBV
- HSV I & II
Foscarnet moa?
Inhibit DNA polymerase
Ganciclovir coadministered to produce synergy?
Foscarnet
Trifluvidine moa?
Replaces Thymidine in viral DNA –> produce fraudulent base pairing
Amantadine & Rimantadine moa?
Inhibit the endosome-mediated uncoating of single stranded RNA viruses prior to transcription and replication.
Amantadine & Rimantadine target organisms?
Orthomyxoviridae
Time frame for administration of Amantadine & Rimantadine?
48 hours after onset of symptoms
Ribavirin moa?
inhibits inosine monophosphate dehydrogenase in viral DNA and RNA polymerases
Zanamivir and Oseltavir moa?
neuroaminidase inhibitor
Zanamivir and Oseltavir target organisms?
acute uncomplicated infection with Influenzae A and B
Antiretrovirals(NNRT) moa?
inhibits HIV-encoded RNA dependent DNA polymerases
Zidovudine(AZT) dose-limiting toxicity?
anemia
Zidovudine(AZT) and pregnancy?
When given in second trimester it reduces vertical transmission by 25%
Antiretrovirals(non-NRTIs) common enzyme inhibition?
CYP3A
HIV-1 protease inhibitors moa?
inhibits protease that cleaves Pol-Gag(essential for viral prolifferation) polyprotein cleavage
HIV-1 protease inhibitor adverse effects?
lipodystrophy and resistance occur
Saquinavir, Ritonavir and Indinavir are all …….
HIV-1 protease inhibitors
Enfurvirtide moa?
binds glycoprotein41 = prevents viral entry to host cell
What are HAARTs?
Highly Active AntiREtroviral Treatment = specific drug regiments
Lamivudine area of use?
prevent hepatic fibrosis by HBV
Imiquimod are of use?
treat anal and genital warts caused by HPV
Treat HBV fibrosis with
Lamivudine
Imiquimod is used to treat ……
Anal and genital warts caused by HPV