Drug interactions
Cefalexin + Typhoid vaccine live
Severity: Moderate
Cefalexin and Typhoid vaccine live: 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
Oral live typhoid vaccine (Ty21a) contains viable attenuated Salmonella Typhi, and antibiotics active against it may reduce its replication and immune response. Protection may be diminished if given during antibacterial therapy.
What this interaction means in plain words
Cefalexin and Typhoid vaccine live 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 kills the attenuated vaccine organism before it can induce immunity.
What to do
Give the oral typhoid vaccine at least 24 hours after the last antibiotic dose, or delay vaccination until antibiotics are completed, per labeling.
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
- Bcg vaccine live + Cefalexin Moderate
- Cefalexin + Cholera vaccine Moderate
- Cefalexin + Kanamycin Moderate
Frequently asked questions
Can I take Cefalexin with Typhoid vaccine live?
MediHelp rates the interaction as moderate. Cefalexin and Typhoid vaccine live 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. Oral live typhoid vaccine (Ty21a) contains viable attenuated Salmonella Typhi, and antibiotics active against it may reduce its replication and immune response. Protection may be diminished if given during antibacterial therapy.
How serious is the interaction between Cefalexin and Typhoid vaccine live?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Give the oral typhoid vaccine at least 24 hours after the last antibiotic dose, or delay vaccination until antibiotics are completed, per labeling.
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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