Question | Answer |
infects and replicates in the upper respiratory tract (epithelium)system b/c climate-cooler temperature | influenza |
influenza | B that infect humans, spread via inhalation (droplets) |
Amantadine, Rimantidine, Oseltamivir (Tamiflu), Zanamivir (Relenza) | Anti-influenza agents |
Amantadine
(anti-influenza agent) | prevent viral uncoding, blocks proton ion channels, active only against TYPE A INFLUENZA, eliminated unchanged in urine, 12-18 hrs, well absorbed, very significant incidence of resistance, cause CNS side effects |
Rimantidine
(anti-influenza agent) | prevent viral uncoding, blocks proton ion channels,active only against TYPE A INFLUENZA, 4-10x more active in vitro, 24-36 hrs, liver metabolize then urine elimination(gets broken down before excreted) |
Amantadine & Rimantidine adverse effects | NVD, anorexia, CNS:nervousness, dizziness, insomnia, decrease concentration, lightheadness (worsened by antihistamines, anticholinergics) |
Which anti-influenza agent cause dopamine effects: behavioral changes, delirium, hallucinations, agitation, seizures | amantadine - interferes with dopamine receptors, has a lipid bilayer so it can cross into the BBB |
Zanamivir (Relenza) & Oseltamivir (Tamiflu)
(anti-influenza agent) | active against both Type A & B influenza, prevent budding (viral release), inhibits viral neuraminidase (keeps virus attached to host cell) to keep virus from infecting other host cells |
necessary for release of newly replicated viruses from the host cell | viral neuraminidase |
Zanamivir
(Relenza:anti-influenza agent) | given to pts > 7 yrs old,poor oral absorption so given via PO inhaler; nose/throat discomfort,bronchospasm,cough,decrease pulmonary fxn; renal excreted, do not use in pts w/airway disease (asthma, COPD, emphysema) |
Oseltamivir
(Tamiflu - anti-influenza agent) | given to pts > 1 yrs old, PO, prodrug activated by hepatic kinases, renally excreted, 6-10hrs, NVD/abd pain less taken with food; high increase resistance |
Neuraminidase Inhibitors | Zanamivir (Relenza) & Oseltamivir (Tamiflu)
(anti-influenza agents) |
Influenza Resistance | mutation in viral neuraminidase; many strains of influenza causing seasonal flu (H1N1) are resistant to amantadine/rimantadine |
Immunization for influenza | given yearly b/c high increase of resistance, influenza vaccine-highly effective |