Two medicines, side by side
Famciclovir vs valacyclovir
Famciclovir and valacyclovir are both labeled for herpes and shingles. Drugs@FDA records approvals of famciclovir since 1994 and of valacyclovir since 1995. Pharmacies paid $0.214 per famciclovir 125 mg tablet and $0.229 per valacyclovir HCl 500 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. In FDA's classes, famciclovir is a herpes simplex virus nucleoside analog dna polymerase inhibitor and valacyclovir a herpes zoster virus nucleoside analog dna polymerase inhibitor.
Check it at the source: the famciclovir FDA label on DailyMed (effective September 17, 2025); the valacyclovir FDA label on DailyMed (effective November 12, 2025).
Highlights of the famciclovir record
Famciclovir (Famvir) · label of September 17, 2025
Used for
From the label: indicationsFamciclovir, a prodrug of penciclovir, is a deoxynucleoside analog DNA polymerase inhibitor indicated for: Immunocompetent Adult Patients ( 1.1 ) • Herpes labialis (cold sores) o Treatment of recurrent episodes • Genital herpes o Treatment of recurrent episodes o Suppressive therapy of recurrent episodes • Herpes zoster (shingles) Human Immunodeficiency Virus (HIV) -Infected Adult Patients ( 1.2 ) • Treatment of […]
On the market
- Earliest approval on file
- June 29, 1994
- Generic labelers
- 9 labelers
- Pharmacy cost
- $0.214 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 3
Highlights of the valacyclovir record
Valacyclovir (Valtrex) · label of November 12, 2025
Used for
From the label: indicationsVALTREX is a deoxynucleoside analogue DNA polymerase inhibitor indicated for: Adult Patients ( 1.1 ) • Cold Sores (Herpes Labialis) • Genital Herpes • Treatment in immunocompetent patients (initial or recurrent episode) • Suppression in immunocompetent or HIV-1−infected patients • Reduction of transmission • Herpes Zoster Pediatric Patients ( 1.2 ) • Cold Sores (Herpes Labialis) • Chickenpox Limitations of Use ( 1.3 […]
On the market
- Earliest approval on file
- June 23, 1995
- Generic labelers
- 40 labelers
- Pharmacy cost
- $0.229 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 4
Source: FDA drug labels via openFDA (Famciclovir label of September 17, 2025, Valacyclovir label of November 12, 2025); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do famciclovir and valacyclovir differ on the record?
In FDA's classes, famciclovir is a herpes simplex virus nucleoside analog dna polymerase inhibitor and valacyclovir a herpes zoster virus nucleoside analog dna polymerase inhibitor.
How each works, in its label's words: Famciclovir, “Famciclovir is an orally administered prodrug of the anti-alpha herpes viral agent penciclovir [ see Microbiology ( 12.4 )].”; Valacyclovir, “Valacyclovir is an antiviral drug active against α-herpes viruses [see Microbiology ( 12.4 )].”
Generics: famciclovir since 2007; valacyclovir since 2007 (Drugs@FDA).
| Famciclovir | Valacyclovir | |
|---|---|---|
| Labeled for | Herpes and shingles | Herpes and shingles |
| Pharmacologic class | Herpes Simplex Virus Nucleoside Analog DNA Polymerase Inhibitor, Herpesvirus Nucleoside Analog DNA Polymerase Inhibitor | Herpes Simplex Virus Nucleoside Analog DNA Polymerase Inhibitor, Herpes Zoster Virus Nucleoside Analog DNA Polymerase Inhibitor, Herpesvirus Nucleoside Analog DNA Polymerase Inhibitor |
| How it works (label) | Famciclovir is an orally administered prodrug of the anti-alpha herpes viral agent penciclovir [ see Microbiology ( 12.4 )]. | Valacyclovir is an antiviral drug active against α-herpes viruses [see Microbiology ( 12.4 )]. |
| Half-life (label) | The plasma elimination half-life of penciclovir was 2.0±0.3 hours after intravenous administration of penciclovir to 48 healthy male volunteers and 2.3±0.4 hours after oral administration of 500 mg famciclovir to 124 … | n/a |
| Earliest approval on file (Drugs@FDA) | June 29, 1994 | June 23, 1995 |
| First generic approved | August 24, 2007 | January 31, 2007 |
| Generic labelers (NDC) | 9 labelers | 40 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.214 per tablet (Famciclovir 125 mg tablet) | $0.229 per tablet (Valacyclovir HCl 500 mg tablet) |
| 12-month price change | -22% | -2% |
| Boxed warning | No | No |
| Shortage now | No current entry | No current entry |
| Recalls recorded | 3 | 4 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 2,753 | 70,054 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What next?
- Alternatives to famciclovir
- every medicine labeled for the same conditions