What the FDA labels say about taking them together
Penicillin g benzathine and probenecid
Penicillin g benzathine's FDA label of July 21, 2026 names probenecid in its drug interactions section; the probenecid label PlainMeds reads does not name penicillin g benzathine. The penicillin g benzathine label: “Concurrent administration of penicillin and probenecid increases and prolongs serum penicillin levels by decreasing the apparent volume of distribution and slowing the rate of excretion by competitively inhibiting renal …”
Check it at the source: the penicillin g benzathine FDA label on DailyMed (effective July 21, 2026, Pfizer Laboratories Div Pfizer Inc); the probenecid FDA label on DailyMed (effective January 5, 2021, Lannett Company, Inc.).
What does the penicillin g benzathine label say about probenecid?
Penicillin g benzathine label, drug interactionsConcurrent administration of penicillin and probenecid increases and prolongs serum penicillin levels by decreasing the apparent volume of distribution and slowing the rate of excretion by competitively inhibiting renal tubular secretion of penicillin.
Source: FDA drug label (BICILLIN L-A), NDA050141 (King Pharms Llc), as published by Pfizer Laboratories Div Pfizer Inc, effective July 21, 2026 (SPL set 012d46f1-d0a0-4676-a879-cd320297ab16), via openFDA; the full label on DailyMed
What does the probenecid label say about penicillin g benzathine?
Probenecid's label (effective January 5, 2021) does not name penicillin g benzathine 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
| Penicillin g benzathine | Probenecid | |
|---|---|---|
| Labeled for | n/a | Gout |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | n/a | $0.636 per tablet 500 mg tablet |
| Shortage now | In shortage | 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