2- Anti-virals and anti-fungal Flashcards
What are the 2 main mechanisms of actions in an anti-viral drug?
Viral enzyme inhibition = blocks the ability of a virus to attach/enter host cells = they can’t replicate In the body
Immune response enhancement = Blocks the ability of a virus to attach & enter host cells
Give 2 examples of anti-viral treatments
Acyclovir - Herpesvirus
Famciclovir - Herpesvirus
Trifluridine - Ocular herpes
Zidovudine - FeLV & FIV
What type of anti-viral is ribavirin?
Broad spectrum- but this does mean there are greater complications with this drug
What is a viricide
inactivates viruses = destroys virus external to host
Disinfectant
List the 4 main anti-fungals groups
Azoles
Allylamines
Polyenes
Pyrimidine analogues
Mechanism of action of azoles
Inhibit Cytochrome P450 dependent synthesis of ergosterol
- causes Cell membrane deficiency - allows toxic products to accumulate = cell death
Mechanism of action of allylamines
Inhibits synthesis of ergosterol via inhibiting squalene epoxidase (enzyme)
- Cell membrane deficiency - allows toxic products to accumulate = cell death
Define ergosterol
sterol that resides on cell membrane & maintain cell membrane integrity
Mechanism of action of Polyenes
Binds to ergosterol - causes pores to be formed in cell membrane - intracellular components leak out = cell death
Mechanism of action of pyrimidine analogues
Inhibition of DNA/RNA synthesis
Name an anti-fungal that would be used in otitis external (malasseia inf.)
Nystatin, Miconazole, Clotrimazole
What anti-fungal agent is in malaseb shampoo used in Malassezia skin infections?
Miconazole
Name a anti-fungal that would be used in ringworm in cats and dogs
Miconazole
Itraconzole (off licence in dogs)
Ketoconazole (off licence in cats- DON’T USE IN CATS)
T/F there are no licensed antifungals in rabbits & small mammals for ringworm
True
Describe what an antiviral agent is
medication that helps the body fight off certain viruses
a preventative measure
large cost associated
List 2 disadvantages of anti-viral drugs
limited safety and efficacy in animals
have narrow therapeutic margin
animal needs to have adequate immune response
what antiviral can be used for most viral infections
feline interferon omega
what antiviral can be used for FIP
caused by coronavirus, remdesivir
what antivirals can be used for FIV
AZT and feline interferon omega
what can be used for feline calicivirus
rebavirin and femile interferon omega
