Drug interactions
Cefalexin + Chloramphenicol
Severity: Minor
Cefalexin and Chloramphenicol: 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
Chloramphenicol is bacteriostatic and cephalexin is bactericidal against actively dividing bacteria, so in theory chloramphenicol could blunt cephalexin's killing effect. The clinical relevance is uncertain and mostly derived from in vitro data.
What this interaction means in plain words
Cefalexin and Chloramphenicol have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Cefalexin belongs to Anti Bacterial; Chloramphenicol belongs to Anti Bacterial.
Why it happens
Theoretical pharmacodynamic antagonism between a bacteriostatic protein synthesis inhibitor and a bactericidal cell wall inhibitor that requires bacterial growth.
What to do
Avoid combining where possible when a bactericidal effect is needed, such as in severe infections; otherwise monitor clinical response to therapy.
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 + Kanamycin Moderate
Other interactions of Chloramphenicol
Frequently asked questions
Can I take Cefalexin with Chloramphenicol?
MediHelp rates the interaction as minor. Cefalexin and Chloramphenicol have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Chloramphenicol is bacteriostatic and cephalexin is bactericidal against actively dividing bacteria, so in theory chloramphenicol could blunt cephalexin's killing effect. The clinical relevance is uncertain and mostly derived from in vitro data.
How serious is the interaction between Cefalexin and Chloramphenicol?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid combining where possible when a bactericidal effect is needed, such as in severe infections; otherwise monitor clinical response to therapy.
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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