Antivirals Flashcards
How are antivirals different from antibacterials?
- Viruses use host cell machinery to replicate, making it difficult to selectively target viral replication.
- The culture for viral replication doesn’t allow for accurate MIC determination, complicating therapeutic dose assessment.
- Antiviral drugs are typically narrow-spectrum, affecting only specific targets.
- Antiviral drugs are all virostatic, as none can be considered virocidal.
True or False: Any viral particles that are not actively replicating will not be affected by antivirals.
True
Antiviral drugs are mostly ___________ spectrum.
Narrow
What is the target of antiviral drugs?
The viral replication cycle
Which antivirals are nucleoside analogs?
Acyclovir, Remdesivir, Idoxuridine, Trifluridine
What is the main immunomodulator used in veterinary medicine?
Imiquimod
What do we mainly use antivirals for in veterinary medicine?
The treatment of herpes keratitis and EHV-1 in horses
What is acyclovir used to treat?
Herpesvirus
What are the adverse effects of acyclovir?
It is toxic to cats at systemic doses; a safer option would be famciclovir.
What is the mechanism of action of acyclovir?
It mimics guanine, terminating DNA elongation and preventing viral replication.
What are idoxuridine and trifluridine used to treat?
Herpes keratitis/cat eye ulcers (use topically)
True or False: L-lysine is controversial and may or may not be effective as an antiviral.
True
What drug can now be used for the treatment of FIP?
Remdesivir
What is remdesivir?
A nucleotide analogue pro-drug (metabolizes into GS-441524)
GS-445124 is a ________________ of remdesivir.
Metabolite (remdesivir is the prodrug)
When should you expect improvement with remdesivir?
24-48 hours (if you don’t see improvement, dose again)
True or False: Injectable GS-441324 is preferred to oral remdesivir when possible.
False. Oral GS-441324 is much safer, do not use an injection.
