Famciclovir Dosage
Generic name: famciclovir
Brand name: Famvir
Drug class: Purine nucleosides
Medically reviewed by A Ras MD.
Recommended Adult Dosing
Dosage forms: TAB: 125 mg, 250 mg, 500 mg
Genital HSV, immunocompetent pts
- [*1st episode]
- Dose: 250 mg PO tid x7-10 days; Info: may extend tx if not healed after 10 days
- [recurrence]
- Dose: 1000 mg PO bid x1 day; Start: ASAP w/in 6h of sx onset; Alt: 500 mg PO x1, then 250 mg PO bid x2 days; 125 mg PO bid x5 days
- [suppression]
- Dose: 250 mg PO bid; Info: reassess tx need at 1y
Genital HSV, immunocompromised pts
- [*1st episode]
- Dose: 500 mg PO bid x7-10 days; Start: ASAP w/in 48h of sx onset
- [recurrence]
- Dose: 500 mg PO bid x5-10 days; Start: ASAP w/in 48h of sx onset
- [*suppression]
- Dose: 500 mg PO bid; Info: reassess tx need at 1y
Orolabial HSV, immunocompetent pts
- [recurrence]
- Dose: 1500 mg PO x1; Start: ASAP after sx onset
Orolabial HSV, immunocompromised pts
- [*1st episode]
- Dose: 500 mg PO bid x5-10 days; Start: ASAP w/in 48h of sx onset
- [recurrence]
- Dose: 500 mg PO bid x7 days; Start: ASAP w/in 48h of sx onset
- [*suppression]
- Dose: 500 mg PO bid; Info: reassess tx need at 1y
Herpes zoster (shingles)
- [500 mg PO tid x7 days]
- Start: ASAP w/in 72h of rash onset, maximum efficacy w/in 48h
Renal dosing
- [genital HSV, immunocompetent pts, 1st episode]
- renal impairment: consider decr. usual dose and/or frequency
- HD: consider decr. usual dose and/or frequency; consider supplement if next maint. dose not due right after dialysis; PD: not defined
- [genital HSV, immunocompetent pts, recurrence]
- CrCl 40-59: 500 mg bid x1 day; CrCl 20-39: 500 mg x1; CrCl <20: 250 mg x1
- HD: 250 mg x1 after dialysis; no supplement; PD: not defined
- [genital HSV, immunocompetent pts, suppression]
- CrCl 20-39: 125 mg bid; CrCl <20: 125 mg qd
- HD: 125 mg 3x/wk after dialysis; consider supplement if next maint. dose not due right after dialysis; PD: not defined
- [orolabial HSV, immunocompetent pts, recurrence]
- CrCl 40-59: 750 mg x1; CrCl 20-39: 500 mg x1; CrCl <20: 250 mg x1
- HD: 250 mg x1 after dialysis; no supplement; PD: not defined
- [genital or orolabial HSV, immunocompromised pts]
- CrCl 20-39: 500 mg qd; CrCl <20: 250 mg qd
- HD: 250 mg 3x/wk after dialysis; consider supplement if next maint. dose not due right after dialysis; PD: not defined
- [herpes zoster (shingles)]
- CrCl 40-59: 500 mg bid; CrCl 20-39: 500 mg qd; CrCl <20: 250 mg qd
- HD: 250 mg 3x/wk after dialysis; consider supplement if next maint. dose not due right after dialysis; PD: not defined
Hepatic dosing
- mild-moderate impairment: no adjustment; severe impairment: not defined
Recommended Peds Dosing
- Dosage forms: TAB: 125 mg, 250 mg, 500 mg
Genital HSV
- [1st episode, preadolescents >45 kg and adolescents]
- Dose: 250 mg PO tid x7-10 days; Info: may extend tx if not healed after 10 days
- [recurrence, preadolescents >45 kg and adolescents]
- Dose: 1000 mg PO bid x1 day; Start: ASAP w/in 6h of sx onset; Alt: 500 mg PO x1, then 250 mg PO bid x2 days; 125 mg PO bid x5 days
- [suppression, preadolescents >45 kg and adolescents]
- Dose: 250 mg PO bid; Info: reassess tx need at 1y
Renal dosing
- [1st episode]
- renal impairment: consider decr. usual dose and/or frequency
- HD: consider decr. usual dose and/or frequency; consider supplement if next maint. dose not due right after dialysis; PD: not defined
- [recurrence]
- CrCl 40-59: 500 mg bid x1 day; CrCl 20-39: 500 mg x1; CrCl <20: 250 mg x1
- HD: 250 mg x1 after dialysis; no supplement; PD: not defined
- [suppression]
- CrCl 20-39: 125 mg bid; CrCl <20: 125 mg qd
- HD: 125 mg 3x/wk after dialysis; consider supplement if next maint. dose not due right after dialysis; PD: not defined
Hepatic dosing
- mild-moderate impairment: no adjustment; severe impairment: not defined
SRC: NLM .