Medication·Interactions & depletion·Reviewed June 9, 2026
Cephalexin interactions.
Cephalexin has 3 documented interactions in the NutriStack database. Prolonged use is also associated with lower Vitamin K. The full interaction list, depletion table, and replacement suggestions are below. None of this is a substitute for your prescriber's advice.
Cephalexin at a glance.
A quick, data-grounded summary. The full tables are below.
Cephalexin has 3 documented interactions in the NutriStack database. Prolonged use is also associated with lower Vitamin K. The full interaction list, depletion table, and replacement suggestions are below. None of this is a substitute for your prescriber's advice.
Substances that interact with cephalexin.
Every supplement and medication in the NutriStack database with a documented interaction with this drug, highest-severity first. Open any pair for the mechanism and sources.
| Substance | Interaction | What happens |
|---|---|---|
| Vitamin K2 | Caution | Broad-spectrum antibiotics including cephalosporins suppress vitamin K-producing gut bacteria, which can lower endogenous vitamin K2 (menaquinone)... details → |
| Probiotics | Synergy | Probiotic supplementation during cephalexin therapy reduces antibiotic-associated diarrhea and helps preserve gut microbiome diversity disrupted by... details → |
| Saccharomyces Boulardii | Synergy | Saccharomyces boulardii reduces antibiotic-associated diarrhea during cephalexin therapy and is unaffected by the antibiotic because it is a yeast. details → |
What cephalexin can deplete.
Nutrients this medication is associated with lowering over time, with the mechanism, a suggested replacement where one applies, and the biomarker to monitor. Discuss any replacement with your prescriber first.
| Nutrient | Severity | How it happens | Replace with | Monitor |
|---|---|---|---|---|
| Vitamin K | Mild | Broad-spectrum antibiotic exposure can suppress gut bacteria that synthesize menaquinones, lowering vitamin K availability in susceptible patients. | – | PT/INR |
The full cephalexin profile.
Uses, typical dosing, side effects, and the cited evidence for this medication.
Common cephalexin questions.
Quick answers drawn from the tables above.
What interacts with Cephalexin?
In the NutriStack database, Cephalexin has 3 documented interactions. The most notable include Vitamin K2, Probiotics, and Saccharomyces Boulardii. Check any specific combination before taking it and confirm with your prescriber.
Does Cephalexin deplete any nutrients?
Cephalexin is associated with lowering Vitamin K with prolonged use. Useful biomarkers to monitor include PT/INR. Ask your prescriber before adding any replacement supplement.
Is it safe to take Vitamin K2 with Cephalexin?
NutriStack classifies the Vitamin K2 and Cephalexin pairing as caution: Broad-spectrum antibiotics including cephalosporins suppress vitamin K-producing gut bacteria, which can lower endogenous vitamin K2 (menaquinone) levels during... For short cephalexin courses in healthy adults, no special action is needed. For prolonged therapy, malnourished patients, or those at bleeding... Always confirm with your prescriber.
Check your whole stack
See how cephalexin fits your supplements.
NutriStack screens your full routine for interactions and depletions, and updates the moment you change it.