Drug interactions
Bcg vaccine live + Cefalexin
Severity: Moderate
Bcg vaccine live 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
Live BCG contains viable bacteria, and antibiotics active against them can reduce vaccine take. Cefalexin has limited activity against BCG, but concurrent antibiotics are generally avoided around live bacterial vaccination.
What this interaction means in plain words
Bcg vaccine live 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
Antibacterial activity may reduce replication of the live vaccine organism, lessening the immune response.
What to do
Defer BCG vaccination until antibiotic therapy is complete, where the vaccine is not urgent.
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
- Balstilimab + Cefalexin Moderate
- Cefalexin + Cholera vaccine Moderate
- Cefalexin + Gentamicin Moderate
- Cefalexin + Kanamycin Moderate
Frequently asked questions
Can I take Bcg vaccine live with Cefalexin?
MediHelp rates the interaction as moderate. Bcg vaccine live 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. Live BCG contains viable bacteria, and antibiotics active against them can reduce vaccine take. Cefalexin has limited activity against BCG, but concurrent antibiotics are generally avoided around live bacterial vaccination.
How serious is the interaction between Bcg vaccine live 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: Defer BCG vaccination until antibiotic therapy is complete, where the vaccine is not urgent.
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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