Cephalexin and Probenecid Interaction
Drug interaction information between Cephalexin and Probenecid.
Cephalexin and Probenecid have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Cephalexin and Probenecid. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Probenecid blocks your kidneys from removing cephalexin from your body. This causes the antibiotic to build up to higher levels than intended.
FDA Label Information
( 7.1 ) Probenecid-The renal excretion of cephalexin is inhibited by probenecid. Co-administration of probenecid with cephalexin is not recommended. 7.2 Probenecid The renal excretion of cephalexin is inhibited by probenecid.
Probenecid Also Interacts With
- Ketorolac major
- Levofloxacin major
- Amoxicillin moderate
- Amoxicillin/Clavulanate moderate
- Ceftazidime/Avibactam moderate
Frequently Asked Questions
What SPL severity band is on file for Cephalexin + Probenecid?
Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Probenecid has 37 labeled pairs on file vs Cephalexin's 2. In the moderate band specifically: Cephalexin has 1; Probenecid has 12 (also Amoxicillin, Amoxicillin/Clavulanate, Ceftazidime/Avibactam, Cefuroxime).
What mechanism field is on file for Cephalexin and Probenecid?
Probenecid blocks your kidneys from removing cephalexin from your body. This causes the antibiotic to build up to higher levels than intended.
Probenecid carries more major-labeled pairs than Cephalexin
SPL source-record counts only. This page's band is moderate · classes on file: Cephalexin (First-Generation Cephalosporin); Probenecid (Uricosuric Agent).
Probenecid has 2 major-labeled pairs vs Cephalexin's 0. This page itself is in the moderate band, not the major band.
0 major · 1 moderate · 1 minor · 2 total
Cephalexin has no other moderate-band peer in this dataset besides Probenecid.
2 major · 12 moderate · 23 minor · 37 total
- Other moderate peers for Probenecid
- Amoxicillin
- Amoxicillin/Clavulanate
- Ceftazidime/Avibactam
- Cefuroxime
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.