Pharmacology Funal and Viral Pneumonia Flashcards
Treatment for Candida albicans
amphotericin B (IV) and fluconazole
Treatment for Cryptococcus neoformans
CNS: amphotericin B (IV) and flucytosine (PO)
Non-CNS: Fluconazole (PO)
Treatment for Aspergillus
Voriconazole IV (step down PO)
2nd: amphotericin B (step down Posconazole PO)
Treatment forBlastomyces dermatitidis
1st line: Fluconazole IV or Amph B IV (step down: voriconazole, itraconazole, fluconazole)
2nd line: amph B IV (step down voriconazole or fluconazole PO)
Treatment for Histoplasma capsulatum
Severe/Immunocompromised: amphotericin B IV followed by Itraconazole PO
Mild/Moderate: Voriconazole or Posaconazole or Fluconazole PO
Treatment for Coccidioides immitis
Severe/Immunocompromised: amphotericin B IV followed by Itraconazole or fluconazole PO
Mild/Moderate: Voriconazole or Posaconazole PO
Amphotericin B issues
nephrotoxicity (try to avoid by putting in lipid medium), hypokalemia
Flucystine issues
hematotoxic - anemia, blood dyscrasias, agranulocytosis
Azole metabolism
CYP2C9, CYP2C19, CYP3A4
Antifungal that crosses blood brain barrier
Fluconazole
Absorption of Itraconazole
oral absorption is low and variable from patient to patient so newer azoles are recommended more
Primary first line antifungals
Azole or Amphotericin B
Indication for Flucytosine
Cryptococcal infections
Reason for Aspergillus resistance to Azoles
mutations in the promoter region of CYP51A which encodes lanosterol 14alpha sterol demthylase activity (the drug target of azoles)
Antifungals that do not undergo hepatic metabolism
Amphotericin B and Flucytosine
Variables suggesting viral cause of pneumonia
younger than 5yo, ongoing epidemic, slow onset, rhinitis, wheezing, normal WBC, low CRP, low pro calcitonin, sole interstitial bilateral infiltrates on CXR, slow/non-responsive to ABX
Treatment for Influenza A and B virus
Oseltamivir (PO) or Zanamivir (inhalation)
Prevention for influenza A and B
Vaccines (inactivated, live); oseltamivir, zanamivir
Treatment of Influenza A virus
Amantadine (PO) or Rimantadine (PO)
Treatment of RSV
Ribavirin (inhalation, IV)
Prevention of RSV
Palivizumab (intramuscular)
Treatment of Adenovirus
Cidofovir (IV)
Prevention of Adenovirus
Vaccine for types 4&7
Prevention of Rhinovirus
Alfa interferon (intranasal); Ribavirin
Treatment/Prevention of Enteroviruses
None
Treatment of human metapneumovirus
Ribavirin (IV)
Treatment of Hantavirus
Ribavirin (IV)
Treatment of Varicella-Zoster virus
Acyclovir (IV) or Valacyclovir (PO)
Prevention of Varicella-Zoster virus
vaccine
Acyclovir MOA
inhibition of viral DNA synthesis (DNA polymerase inhibition)
Amantadine MOA
inhibition of viral entry or uncoating
Cidofovir MOA
inhibition of viral DNA synthesis
Oseltamavir MOA
inhibition of release of influenza virus from infected cell
Ribavirin MOA
inhibition of viral nucleic acid synthesis
Rimantadine MOA
inhibition of viral entry or uncoating
Valacyclovir MOA
pro-drug from acyclovir
Zanamivir MOA
inhibition of release of influenza virus from infected cell
Acyclovir metabolism
Viral cells transform acyclovir to its active triphosphate form; systemic elimination unchanged by glomerular filtration and tubular secretion
Amantadine metabolism
systemic elimination unchanged by glomerular filtration and tubular secretion
Cidofovir metabolism
metabolized via pyriminidine nucleoside monophosphate kinase to mono and then diphosphate analogs and finally to the monophosphate choline; systemic elimination by glomerular filtration and tubular secretion
Oseltamavir metabolism
hepatically metabolized to the carboxylate active form of the drug; systemic elimination by glomerular filtration and tubular secretion
Ribavirin metabolism
undergoes non-CYP metabolism in nucleated cells with systemic elimination of drug and products in the urine
Rimantadine metabolism
extensive hepatic metabolism with renal elimination of drug and metabolites
Valacyclovir metabolism
Converted ot acyclovir and L-valine by 1st pass metabolism; systemic elimination of acyclovir by glomerular filtration and tubular secretion
Zanamivir metabolism
renal elimination unchanged
Acyclovir toxicities
HA, nausea, elevated hepatic enzymes, nasopharyngitis, neutropenia; maintain hydration to prevent renal precipitation; se cautiously in renal impairment or with reno-toxic drugs
Amantadine toxicities
Neurologic, nausea, orthostatic hypotension, contra in narrow angle glaucoma and with breast feeding
Cidofovir toxicities
neurologic, hematologic and tubular damage; Black box warning for renal impairment/toxicities
Oseltamavir toxicities
minimal; potential for fatal neuropsychiatric adverse effects in flue patients; serious skin reaction reported rarely
Ribavirin toxicities
fatigue, headache, myalgia, nausea, fever; Black Box - hemolytic anemia and M/F teratogenicity
Rimantadine toxicities
Minimal adverse effects
Valacylovir toxicities
HA, nausea, elevated hepatic enzymes, nasopharyngitis, neutropenia; hydrate to avoid renal precipitation; use cautiously in patients with renal impairment or renal toxic drugs
Zanamivir toxicities
HA, throat/tonsil pain, cough, viral infection, NOT to be used with underlying pulmonary disease due to Fatal Bronchospasm