Drugs to Treat Influenza (J-Staud) Flashcards
MOA of Neuraminidase Inhibitors
Inhibit viral neuraminidase enzymes.
This prevents viral reproduction by budding from the host cell.
(NA cleaves sialic acid which is found on glycoproteins on the surface of human cells that helps new virions to exit the cell)
Indication of oral osteltamivir
Influenza A and B infections in patients that have been symptomatic for no more than 48 hours.
Prophylaxis of influenza
Contraindications of Osteltamivir?
End-stage renal disease
Warnings and precautions of Osteltamivir?
Serious bacterial infections
Don’t give flu vaccine within 2 weeks before or 48 hours after osteltamivir is given.
Limitation of osteltamivir?
Not a substitute for early influenza vaccination
Can you give osteltamivir to young children?
not indicated to treat flu in younger than 2 weeks.
Not indicated to prevent flu in kids younger than 1 year old.
Metabolism of oral osteltamivir?
NOT a substrate for or inhibitor of cytochrome P450 or UDG-Glucuronosyl Transferase (UGT) enzyme isoforms.
Route of administration of Zanamivir?
Inhalation
Use of Zanamivir?
Give to treate acute uncomplicated illness due to Influenza A and B virus in patients 7 years and older. (not recommended if younger than 12 tho)
Contraindications of inhaled zanamivir?
Seizures or history of seizures
Lung disease
Warnings & Precautions of inhaled zanamivir?
Does not prevent bacterial infection that starts with flu like symptoms
If live nasal flu vaccine is planned, patient should not receive the vaccine within two weeks before or 48 hours after using this medicine.
Pregnancy indication Inhaled Zanamivir?
Women in any trimester of their pregnancy who have suspected or confirmed influenza should receive prompt antiviral therapy with Tamiflu or Relenza.
Metabolism of Zanamivir?
Kidney, undergoes no metabolic biotransformation
Not a substrate of CYPP450 or isoenzymes
How is Peramivir administered?
IV
MOA of Peramivir?
Neuraminidase inhibitor
Indication of peramivir? Age?
Acute uncomplicated influenza in patients 18 years and older who have been symptomatic for no more than 2 days
Contraindication of peramivir?
Hypersensitivity
Warning and precautions of peramivir?
Neuropsychiatric events
Is peramivir safe for pregnant patients?
Should only be used if clearly indicated
Should peramivir be used in geratric patients?
Yes
Adjust dose if they have impaired renal function
Metabolism of peramivir?
Not a substrate for CYP
Long half-life
Indication of Baloxavir?
Acute uncomplicated influenza
MOA of Baloxavir?
Polymerase acidic endonuclease inhibitor (inhibits virus mRNA replication)
Indications of Baloxavir?
patients that are 12 years of age and older who have been symptomatic no more than 48 hours
Warnings and precautions of Baloxavir?
Risk of bacterial infection
Metabolism of Baloxavir
UGT1A3, CYP3A4
Excretion of Baloxavir
- 7% in urine
80. 1% in feces
Class of amantidine?
Anti-viral and Anti-parkinson; MOA is not known, probably by interfering with the function of the transmembrane domain of the viral M2 protein
Indication of Amantadine?
Prophylaxis and treatment of signs and symptoms of infection caused by various strains of influenza A virus
Why do we have to be careful in dosing of Amantadine?
Lowest reported acute lethal dose was 1 gram
Overdose results in cardiac, respiratory, renal, or CNS toxicity
(Cardiac dysfunction includes arrhythmia, tachycardia, and HTN)
Why do we have to be careful using Amantadine in patients with mental problems?
Can exacerbate them in patients with mental history or substance abuse history.
Increased risk of suicide.
Why do we have to be careful of patients with CNS history when giving Amantadine?
Pts with history of epilepsy may have increased incidence of seizure.
Pts with CNS history should be cautioned against working or driving while taking.
Amantadine has anticholinergic effects, because of this, it should not be given to patients with what condition?
untreated angle closure glaucoma
What must we be careful of doing in patients taking amantadine with Parkinson’s?
Abruptly discontinuing. Can cause Parkinsonian crisis.
Or delirium, agitation, delusions, hallucinations, paranoid reaction, stupor, anxiety, depression, and slurred speech
The early diagnosis of what condition is important when considering Amantadine or discontinuing amantadine?
Neuroleptic malignant syndrome
fever, muscle rigidity, involuntary movements, altered consciousness, mental status change
Is renal disease a concern with Amantadine?
yes, with decreased function it accumulates in the plasma and in the body when renal fx declines.
(reduce in patients with renal impairment and in individuals who are 65 years or older.)
Is liver disease a concern with amantadine?
Yes, reversible elevation of liver enzymes have been reported in patients receiving amantadine.
What skin condition should be monitored in patients with Parkinson’s or anyone taking amantadine?
Melanoma
Metabolism of Amantadine?
No P450s or UGT enzymes.
Mean half life is 10 to 14 hours
(Renal function can increased 7 to 10 days)
