Drug interactions
Balstilimab + Cefalexin
Severity: Moderate
Balstilimab and Cefalexin: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Observational data suggest that antibiotic exposure around the start of checkpoint inhibitor therapy may be associated with poorer outcomes, possibly through disruption of the gut microbiome. The association is not proven to be causal and is based on retrospective data.
What this interaction means in plain words
Balstilimab and Cefalexin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Antibiotic-induced gut dysbiosis may alter systemic immune responses to checkpoint blockade, but the mechanism is not established.
What to do
Prescribe antibiotics only when clearly indicated and use the shortest effective course. Do not withhold needed antibiotic treatment; monitor oncologic response.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Cefalexin
- Amikacin + Cefalexin Moderate
- Avelumab + Cefalexin Moderate
- Bcg vaccine live + Cefalexin Moderate
- Cefalexin + Cholera vaccine Moderate
- Cefalexin + Gentamicin Moderate
- Cefalexin + Kanamycin Moderate
Frequently asked questions
Can I take Balstilimab with Cefalexin?
MediHelp rates the interaction as moderate. Balstilimab and Cefalexin can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Observational data suggest that antibiotic exposure around the start of checkpoint inhibitor therapy may be associated with poorer outcomes, possibly through disruption of the gut microbiome. The association is not proven to be causal and is based on retrospective data.
How serious is the interaction between Balstilimab and Cefalexin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Prescribe antibiotics only when clearly indicated and use the shortest effective course. Do not withhold needed antibiotic treatment; monitor oncologic response.
What other medicines interact with Cefalexin?
MediHelp also lists interactions of Cefalexin with, for example, Amikacin, Avelumab, Bcg vaccine live. The full list is on the Cefalexin page.
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