What the FDA labels say about taking them together
Famciclovir and probenecid
Famciclovir's FDA label of September 17, 2025 names probenecid in its drug interactions section; the probenecid label PlainMeds reads does not name famciclovir. The famciclovir label: “DRUG INTERACTIONS Probenecid: May increase penciclovir levels. Monitor for evidence of penciclovir toxicity”
Check it at the source: the famciclovir FDA label on DailyMed (effective September 17, 2025, Macleods Pharmaceuticals Limited); the probenecid FDA label on DailyMed (effective January 5, 2021, Lannett Company, Inc.).
What does the famciclovir label say about probenecid?
Famciclovir label, drug interactionsDRUG INTERACTIONS Probenecid: May increase penciclovir levels. Monitor for evidence of penciclovir toxicity
Source: FDA drug label (Famciclovir), Macleods Pharmaceuticals Limited, effective September 17, 2025 (SPL set eeeee9c4-8566-4100-8ca4-3df936a3365d), via openFDA; the full label on DailyMed
What does the probenecid label say about famciclovir?
Probenecid's label (effective January 5, 2021) does not name famciclovir in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Probenecid), Lannett Company, Inc., effective January 5, 2021 (SPL set ab497fd8-00c3-4364-b003-b39d21fbdf38), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Famciclovir | Probenecid | |
|---|---|---|
| Labeled for | Herpes and shingles | Gout |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.214 per tablet 125 mg tablet | $0.636 per tablet 500 mg tablet |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once