chapter 24 antivirals

Question 1

pharmacodynamics of antivirals

Answer 1

acyclovir: active against HSV 1 and 2; varicella-zoster virus, epstein-barr virus, cmv, herpes virus 6
valacyclovir: converts to acyclovir after po administration
famciclovir: active against HSV-1 and 2, varicella zoster, epstein-barr, hep b
ganciclovir: CMV

Question 2

ADRs of antivirals

Answer 2

valacyclovir: thrombocytopenia purpura, hemolytic uremic syndrome in immunocompromised pt
- head aches
- ganciclovir: granulocytopenia, anemia, thrombocytopenia, can cause carcinogens

Question 3

clinical use/dosing for antivirals

Answer 3

• herpes: genital herpes for initial outbreak and suppression therapy
• herpes zoster: within 3 days of outbreak
• varicella: within 24 hours of outbreak
• gingivostomatitis in children
• bells palsey
• monitoring: bun/creat for high risk patients

Question 4

antivirals

Answer 4

• virus dependent on host genetic material to replicate-drugs must either prevent entering host cell or reside within host cells itself
• nonselective drugs-damage to host cell as well
• viral replication peaks before symptoms occur with optimal drug efficacy

Question 5

pharmacodynamics/pharmacokinetics for antivirals for influenza

Answer 5

• Amatadine (Symmetrel), rimantadine (Flumadine), and Oseltamivir (Tamiflu) used to treat influenza A
• influenza A and B-Zanamivir (Relenza)-inhaled (4-17% absorption rate)

Question 6

ADRs for antivirals for influenza

Answer 6

• amantadine and ramantadine: CNS/psychic disturbances
• amantadine: HF, peripheral edema
• CDC updates for prescribing

Question 7

monitoring on antivirals for influenza

Answer 7

• renal function in elderly
• amantadine or rimantadine: assess for irritability and seizure activity
• older pt: confusion, hallucination, cognitive impairment