Drug interactions
Atezolizumab + Cefalexin
Severity: Minor
Atezolizumab and Cefalexin: minor 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 link antibiotic exposure around the start of immune checkpoint inhibitor therapy with poorer outcomes, possibly through gut microbiome disruption. The evidence is associative and confounded by patient illness severity. The effect on any individual patient is uncertain.
What this interaction means in plain words
Atezolizumab and Cefalexin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Atezolizumab belongs to Oncology; Cefalexin belongs to Anti Bacterial.
Why it happens
Proposed disruption of gut microbiota that may modulate antitumor immune response; not firmly established.
What to do
Prescribe the antibiotic only when clearly indicated and keep the course short. Do not withhold needed antibiotics.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Cefalexin
- Amikacin + Cefalexin Moderate
- Avelumab + Cefalexin Moderate
- Balstilimab + Cefalexin Moderate
- Bcg vaccine live + Cefalexin Moderate
- Cefalexin + Cholera vaccine Moderate
- Cefalexin + Gentamicin Moderate
Other interactions of Atezolizumab
Frequently asked questions
Can I take Atezolizumab with Cefalexin?
MediHelp rates the interaction as minor. Atezolizumab and Cefalexin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Observational data link antibiotic exposure around the start of immune checkpoint inhibitor therapy with poorer outcomes, possibly through gut microbiome disruption. The evidence is associative and confounded by patient illness severity. The effect on any individual patient is uncertain.
How serious is the interaction between Atezolizumab and Cefalexin?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Prescribe the antibiotic only when clearly indicated and keep the course short. Do not withhold needed antibiotics.
What other medicines interact with Cefalexin?
MediHelp also lists interactions of Cefalexin with, for example, Amikacin, Avelumab, Balstilimab. The full list is on the Cefalexin page.
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