Other Antivirals

Question 1

Amantadine

Answer 1

1. Blocks attachment, penetration, and uncoating of influenza A virus
2. May decrease duration of flu symptoms but mainly used for prophylaxis

Question 2

Side effects of Amantadine

Answer 2

Strong anti-muscarinic and DA release/reuptake blocker:

CNS effects (seizures in OD)

Atropine-like peripheral effects and livedo reticularis

Question 3

Zanamivir and Oseltamivir

Answer 3

Inhibit neuraminidases of influenza A and B (enzymes that prevent clumping of virions so that more particles are available for infecting host cells)

Same clinical use as amantadine (ironically side effects = flu symptoms)

Question 4

Ribavirin

Answer 4

Monophosphorylated form inhibits IMP dehydrogenase

Triphosphate inhibits viral RNA polymerase and end-capping of viral RNA

Question 5

Clinical uses of ribavirin

Answer 5

Adjunct to alpha interferons in hep C

Management of respiratory syncytial virus

Lassa fever

Hantavirus

Question 6

Side effects of Ribavirin

Answer 6

Hematotoxic

Upper airway irritation

Teratogenic

Question 7

Human Interferons

Answer 7

Antiviral: hep B, C, and D

Antitumor: Kaposi sarcoma, CML, MM, renal carcinoma

Immunoregulatory: MS