Drug interactions
Dicloxacillin + Methotrexate
Severity: Moderate
Dicloxacillin and Methotrexate: 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
Penicillins can raise methotrexate blood levels and prolong its exposure. This may lead to bone marrow suppression and gastrointestinal toxicity, particularly with high-dose methotrexate or reduced kidney function.
What this interaction means in plain words
Dicloxacillin and Methotrexate 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.
Dicloxacillin belongs to Anti Bacterial; Methotrexate belongs to Oncology.
Why it happens
Penicillins compete with methotrexate for renal tubular secretion, reducing its renal clearance.
What to do
Monitor blood counts, renal function and methotrexate levels where available. Consider an alternative antibiotic or reduce methotrexate dose if toxicity develops.
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 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
Other interactions of Dicloxacillin
- Dicloxacillin + Phenindione Major
- Atogepant + Dicloxacillin Moderate
- Axitinib + Dicloxacillin Moderate
- Bcg vaccine live + Dicloxacillin Moderate
- Cholera vaccine + Dicloxacillin Moderate
- Demeclocycline + Dicloxacillin Moderate
Frequently asked questions
Can I take Dicloxacillin with Methotrexate?
MediHelp rates the interaction as moderate. Dicloxacillin and Methotrexate 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. Penicillins can raise methotrexate blood levels and prolong its exposure. This may lead to bone marrow suppression and gastrointestinal toxicity, particularly with high-dose methotrexate or reduced kidney function.
How serious is the interaction between Dicloxacillin and Methotrexate?
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 blood counts, renal function and methotrexate levels where available. Consider an alternative antibiotic or reduce methotrexate dose if toxicity develops.
What other medicines interact with Methotrexate?
MediHelp also lists interactions of Methotrexate with, for example, Acitretin, Adenovirus types 4 and 7 live, Influenza virus vaccine quadrivalent intranasal. The full list is on the Methotrexate page.
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