ID 3 pt 2: Antivirals

Question 1

Oseltamivir brand, drug class, dose, side effects

Answer 1

Tamiflu
Neuraminidase inhibitor
> 12 yrs: 75 mg BID x 5 days
Prophylaxis > 12 yrs: 75 mg PO x 10 days
Pediatric (2 wks to 12 yrs): weight based 
CrCL < 60 adjustment required

Side effects: headache, vomiting

Question 2

Zanamivir brand, drug class, dose, warnings

Answer 2

Relenza Diskhaler
Neuramidase inhibitor
Dosed 2 inhalations (5 mg each) BID x 5 days
Prophylaxis 2 inhalations once daily x 10 days (household setting) or 28 days (community outbreak)

Warnings: Bronchospasm (do not use in COPD/asthma or anyone with breathing problems)

Question 3

Peramivir brand, drug class, dose

Answer 3

Rapivab
Neuramidase inhibitor
600 mg IV single dose (underlined)
CrCL < 50 mL/min: adjust dose

Question 4

Rimantadine place in therapy

Answer 4

Treatment prophylaxis only

100 mg BID

Question 5

Acyclovir brand, side effects, notes

Answer 5

Zovirax

Side effects: headaches, malaise, N/V/D, increased SCr, IV inc seizure risk

Acyclovir dose based on IBW in obese patients

Question 6

Valacyclovir brand, side effects

Answer 6

Valtrex

Side effects: headaches, malaise, N/V/D, increased SCr

Question 7

Acyclovir, valacyclovir coverage

Answer 7

Herpes Simplex, Varicella

Question 8

Genital herpes treatment timeline, considerations

Answer 8

To gain full benefit, treatment must be initiated during prodrome or within 1 day of lesion onset

Acyclovir is dosed up to 5x daily, valacyclovir is the prodrug of acyclovir and results in higher concentrations thus less frequent dosing (better adherence)

If resistant to acyclovir, will be resistant to valacyclovir, famciclovir

Question 9

Treatment of invasive HSV infections

Answer 9

IV acyclovir

10 mg/kg/dose q8h x 14-21 days

Question 10

Topical treatment of cold sores

Answer 10

Abreva (OTC) - Docosanol - apply 5x daily until healed

Acyclovir topical cream (Rx) - Zovirax - 5x daily for 4 days

Acyclovir buccal tablet (Rx) - Sitavig - apply 50 mg as single dose to upper gum region

Penciclovir topical cream (Rx) - Denavir - apply q2h during waking hours for 4 days

Question 11

Systemic treatment of cold sores

Answer 11

Initial episode:
Acyclovir 200-400 mg 5x daily or 400 mg TID x 7-10 days
Valacyclovir 2 g PO BID x 1 day

Recurrent: Acyclovir, valacyclovir same doses or famciclovir 1.5 mg PO x 1 doe

Chronic suppression: Acyclovir only, 400 mg PO BID

Question 12

Treatment of shingles

Answer 12

Acyclovir 800 mg PO 5x daily for 7-10 days

Famciclovir 500 mg PO TID for 7 days

Valacyclovir 1 g PO TID for 7 days

Most effective when started within 72 hours

Question 13

What is CMV, how do we treat

Answer 13

Cytomegalovirus, double stranded DNA virus within the herpes virus family
Occurs in severely immunocompromised states
Most commonly causes retinitis, colitis, esophagitis

Ganciclovir and valganciclovir are the treatments of choice for CMV disease

Question 14

Ganciclovir, valganciclovir brands, dosage forms, boxed warnings, notes

Answer 14

Ganciclovir = cytovene
Valganciclovir = Valcyte (prodrug, good oral vbioavailibility)

Ganciclovir = IV only
Valganciclovir = PO only, available as suspension or tab

Boxed warnings = myelosuppression
Side effects = thrombocytopenia, neutropenia, leukopenia, anemia

Question 15

Foscarnet brand, boxed warnings, side effects, place in therapy

Answer 15

Foscavir
Boxed warnings: renal impairment (some degree in majority of patients), seizures due to electrolyte imbalances

Side effects: inc SCr, dec K Ca Mg and Phos

Reserved for refractory CMV failing ganciclovir, valganciclovir

Question 16

Cidofovir boxed warning, place in therapy

Answer 16

Nephrotoxicity

Reserved for refractory CMV failing ganciclovir, valganciclovir

Question 17

Treatment for mononucleosis

Answer 17

Epstein-barr virus, “mono”
Spread by saliva, kissing
No drug treatment or vaccine exists
Resolves on its own in 2-4 weeks