Antivirals Flashcards
What are the 5 mechanisms of action of different antivirals
1) To inhibit penetration/fusion and uncoating
2) To inhibit viral DNA/RNA synthesis (transcription)
3) To inhibit viral protein synthesis
4) To inhibit the release of viral particles
5) Interferons.
What are examples of drugs which inhibit penetration/fusion and uncoating of virus’
- Amantadine
- Enfuvirtide/maraviroc
What is amantadine used to treat
Influenza A
What is the mechanism of action of amantadine
Amantadine interferes with viral protein channels and effects uncoating of viruses
What are the adverse effects of amantadine
Insomnia and depression, especially in the elderly
What are enfuvirtide/maraviroc used to treat
HIV
What is the mechanism of action of maraviroc
It affects the chemokine co-receptor 5 on CD4 cells
What is the mechanism of action of enfuvirtide
It affects gp41 attachment
What are the side effects of enfuvirtide/maraviroc
Injection site reactions.
What are 6 examples of antivirals which inhibit viral DNA/RNA synthesis (transcription)
- Aciclovir
- Ribavirin
- Zidovudine
- Nevirapine
- Efacrine
- Etravarine
What is aciclovir used to treat
Herpes Simplex Virus
What is the mechanism of action of aciclovir
Treatment and prophylaxis.
Viral DNA synthesis is halted so there is premature chain termination, and viral DNA polymerase is irreversibly inactivated.
What are the adverse effects of aciclovir
Aciclovir has relatively low toxicity but resistance can occur.
What does ribavirin do
It is an antiviral which inhibits viral transcription.
What is ribavirin used to treat
- Severe RSV in babies
- Lassa
- Marburg
- Ebola
- Hep C
What four antiviral drugs with the mechanism of action to inhibit viral transcription are used to treat HIV
Zidovudine, nevirapine, efacrine, etravarine
What is the name of a drug that inhibits viral protein synthesis (translation)
Ritonavir
What is ritonavir used to treat
HIV
What are two drugs which inhibit the release of viral particles
Oseltamivir (Tamiflu) and zanamivir
What are oseltamivir and zanamivir used to treat
Influenza A and B
What is the mechanism of action of oseltamivir and zanamivir (antivirals which inhibit the release of viral particles)
They inhibit neuraminidase preventing the release of viral particles. They are used for prophylaxis during pandemics.
What are interferons used to treat
Chronic hepatitis B and C
What is the mechanism of action of interferons
Interferons are immunomodulators produced by the body in response to infection. They affect the production of cellular proteins which act at different stages of the viral cycle.
What are the adverse effects of interferons
Flu like symptoms.
