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
