Exam 2: Antivirals Flashcards
Therapeutic use: Tx of herpes and varicella zoster.
MOA: viral thymidine kinase phosphorylates–>acyclovir triphosphate=>premature chain termination
AE/Toxicity: NV, HA, diarrhea, renal dysfunction–>keep pts hydrated!!
Resistance: altered or deficient thymidine kinase r polymerase
Notes: t1/2 is 2.5h
Tx of HSV, VZV, and Megalovirus
Acyclovir
Therapeutic Use: CMV retinitis and prevention of CMV in transplant pt.
MOA: Inhibits DNA polymerase–>block chain elongation
AE/Toxicity: dose-dependent neutropenia, CNS effects, carcinogenic.
Resistance:
Notes: t1/2 is 24 hrs, more potent than acyclovir. “Gang” up on CMV!
Tx of HSV, VZV, and Megalovirus
Ganciclovir
Therapeutic Use: IV Tx for CMV retinitis in HIV pt who are resistant to ganciclovir and herpes pts who are resistant to acyclovir
MOA: Blocks DNA replication and RNA transcription.
AE Toxicity: nephrotoxicity, anemia, nausea, fever, hypocalemia, hypomagnesia.
Resistance:
Notes: Second-line therapy
Tx of HSV, VZV, and Megalovirus
Foscarnet
Therapeutic Use: HSV keratoconjunctivitis and keratitis. MOA: Blocks viral DNA replication AE Toxicity: inflammation to cornea. Resistance: Notes: Replaced Idoxuridine
Tx of HSV, VZV, and Megalovirus
Trifluridine
Therapeutic Use: shorten duration and prevent flu
MOA: inhibit neuraminidase=decr release of virus from infected cells, incr formation of viral aggregates, and decr viral spread
AE Toxicity: nasal/throat discomfort; bronchospasm
Resistance:
Notes: OZ has the flu!
Neuraminidase Inhibitors
tx viral respiratory inf
Zanamivir
Therapeutic Use: shorten duration and prevent flu.
MOA: inhibit neuraminidase=decr release of virus from infected cells, incr formation of viral aggregates, and decr viral spread
AE/Toxicity: NV, HA
Resistance:
Notes: Good for both influenza A and B; take with food=less nausea
Neuraminidase Inhibitors
tx viral resp inf
Oseltamivir (Tamiflu)
Therapeutic Use: genital warts, chronic hep B & C, Kaposi’s sarcoma (HHV-8), multiple melanomas, multiple sclerosis.
MOA: activate JAK-STAT pathway; induce 2 enzymes=inhibit protein synthesis.
AE/Toxicity: flu-like, bone marrow suppression, fatigue, increased susceptibility to bacterial infections, psychiatric symptoms.
Resistance:
Notes: Peg-IFN 2A WITH Ribavirin is Tx of choice for chronic hep C.
tx of hep viral inf
Interferons
Therapeutic Use: chronic hep C, RSV, flu A & B, parainfluenza A & B, paramyxovirus, arenavirus, HIV==>RIBAvirin – RSV, Influenza B, Arenavirus
MOA: inhibits viral mRNA synthesis
AE Toxicity: anemia, teratogenic=don’t give if pregnant
Resistance:
Notes: Standard choice for hep C; give with IFN
tx of hep viral inf
Ribavirin
Therapeutic Use: most freq given to HIV pt; protect fetus from HIV infected mother.
MOA: NRTI
AE Toxicity: bone marrow suppression, HA, potentially fatal lactic acidosis.
Resistance: mutated rev. transcriptase will have a lower affinity for AZT-TP
Notes: Probenecid, Acetaminophen, Lorazepam, Indomethacin, Cimetidine increase toxicity=>“I am a PAL I Care”
Trizivir: Zidovudine (AZT), Lamivudine (3-TC), and Abacavir
Zidovudine (AZT)
Therapeutic Use: pt with AZT-resistant HIV infection.
MOA: NRTI
AE Toxicity: Pancreatitis, potentially fatal non-cirrhotic portal hypertension.
Resistance: mutated reverse transcriptase
Notes: DO NOT use as first-line therapy; toxicity increased with stavudine.
Didanosine (ddI)
Therapeutic Use: give with AZT or alone if pt can't tolerate AZT. MOA: NRTI AE Toxicity: Peripheral neuropathy Resistance: Notes: The ZZ is given together.
Zalcitabine (ddC)
peripheral neuropathy toxicity with potentially fatal lactic acidosis with AZT.
Stavudine
Zidovudine, Abacavir, Lamivudine–>TriZAL
Trizivir
Therapeutic Use: Pt with HIV in combo with AZT and/or hep B.
MOA: NRTI
AE Toxicity: Pancreatitis in peds.
Resistance:
Notes: part of Trizivir. Reduces chance pt becomes resistant to AZT.
Lamivudine (3-TC)
Therapeutic Use: HIV adults and peds in combo with AZT and lamivudine or protease inhibitor.
MOA: NRTI
AE Toxicity: Hypersensitivity resulting in fever, GI distress, malaise and rash.
Resistance:
Notes: part of Trizivir
Abacavir
Therapeutic Use: HIV pt and chronic hep B. Can prevent HIV prophylactically.
MOA: NtRTI (nucleotide reverse transcriptase inhibitor) and terminates DNA elongation.
AE Toxicity:
Resistance:
Notes: Do not give as didanosine, lamivudin, or abacavir combo. Gel for vagina
Tenofovir
Therapeutic Use: used in combo with AZT and lamivudine for HIV.
MOA: NNRTI; alters conformation of reverse transcriptase.
AE Toxicity: dizziness, HA, insomnia, rash
Resistance:
Notes: Co-admin with Rifampin will reduce levels. Efavirenz can lower [] of many drugs.
Non-Nucleoside Reverse Transcriptase Inhibitos (NNRTIs)
Efavirenz
Therapeutic Use: use in combo with Didanosine or Stavudine
MOA: Alters conformation of reverse transcriptase.
AE Toxicity: Rash
Resistance: Don’t ever take St. John’s Wart, its Stupid! Lowers ethinyl estradiol (estrogen) levels with birth control pills.
Notes: Nevir take St. John’s Wart and change birth control with Nevirapine, cause John likes to go bareback!
Non-Nucleoside Reverse Transcriptase Inhibitos (NNRTIs)
Nevirapine
Therapeutic Use: used in combo with Zidovudine and Didanosine
MOA: NNRTI; binds and inhibits rev. transcriptase of HIV.
AE Toxicity: many effects on various CYPs
Resistance:
Notes: least potent NNRTI
Delaviridine
Therapeutic Use: treat HIV that are resistant to multiple protease inhibitors.
MOA: Protease inhibitors.
AE Toxicity: Diarrhea, N /F/ HA, hyperlipidemia, hyperglycemia, altered body fat.
Resistance: Has CYP effects.
Notes: Ritonavir inhibits CYP 3A4 so it raises levels of Lopinavir.
Lopinavir / Ritonavir
Therapeutic Use: injected daily in HIV pt.
MOA: Fusion inhibitor
AE Toxicity: pain, redness, nodule, cysts at injection.
Resistance:
Notes:
Enfuvirtide
Therapeutic Use: HIV pt MOA: Fusion inhibitor AE Toxicity: cough, fever, dizziness, HA, lowered BP, nausea, and bladder irritation. Resistance: Notes:
Maraviroc
