Drug interactions
Methotrexate + Neomycin
Severity: Moderate
Methotrexate and Neomycin: 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 neomycin can reduce the absorption of oral methotrexate, which may lower its effect. It may also disturb gut flora involved in methotrexate handling. The result is potentially reduced efficacy of oral methotrexate, particularly at higher doses.
What this interaction means in plain words
Methotrexate and Neomycin 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.
Methotrexate belongs to Oncology; Neomycin belongs to Anti Bacterial.
Why it happens
Neomycin causes malabsorption through effects on the intestinal mucosa and suppresses gut flora involved in methotrexate recirculation.
What to do
Monitor clinical response to methotrexate during neomycin therapy. Consider separating doses or switching to parenteral methotrexate if efficacy is reduced.
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 Neomycin
- Amikacin + Neomycin Major
- Amphotericin b deoxycholate + Neomycin Major
- Capreomycin + Neomycin Major
- Cidofovir + Neomycin Major
- Colistin + Neomycin Major
- Ethacrynic acid + Neomycin Major
Other interactions of Methotrexate
- Acitretin + Methotrexate Contraindicated
- Adenovirus types 4 and 7 live + Methotrexate Contraindicated
- Influenza virus vaccine quadrivalent intranasal + Methotrexate Contraindicated
- Ketorolac + Methotrexate Contraindicated
- Measles mumps and rubella vaccine live + Methotrexate Contraindicated
- Measles mumps and rubella vaccine + Methotrexate Contraindicated
Frequently asked questions
Can I take Methotrexate with Neomycin?
MediHelp rates the interaction as moderate. Methotrexate and Neomycin 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 neomycin can reduce the absorption of oral methotrexate, which may lower its effect. It may also disturb gut flora involved in methotrexate handling. The result is potentially reduced efficacy of oral methotrexate, particularly at higher doses.
How serious is the interaction between Methotrexate and Neomycin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor clinical response to methotrexate during neomycin therapy. Consider separating doses or switching to parenteral methotrexate if efficacy is reduced.
What other medicines interact with Neomycin?
MediHelp also lists interactions of Neomycin with, for example, Amikacin, Amphotericin b deoxycholate, Capreomycin. The full list is on the Neomycin page.
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