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Drug interactions

Ifosfamide + Methotrexate

Severity: Major

Ifosfamide and Methotrexate: major 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

Both agents are cytotoxic and cause myelosuppression and immunosuppression, so combination raises the risk of severe cytopenias and infection. Ifosfamide may also cause nephrotoxicity, which could delay methotrexate clearance.

What this interaction means in plain words

Ifosfamide and Methotrexate can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.

Ifosfamide belongs to Oncology; Methotrexate belongs to Oncology.

Evidence level: Moderate

Why it happens

Additive myelosuppression and immunosuppression, with ifosfamide nephrotoxicity potentially reducing methotrexate elimination.

What to do

Monitor blood counts, renal function and methotrexate levels closely, and adjust doses per the chemotherapy protocol. Provide supportive care and infection prophylaxis as indicated.

What to ask your pharmacist

  • Does the benefit of taking both outweigh the risk in my case?
  • Do I need any blood test, ECG or other check while on both?
  • What early warning signs should I watch for, and what should I do if they appear?

Bring a full list of your medicines, including over-the-counter products, supplements and herbal remedies, to every pharmacy visit.

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Frequently asked questions

Can I take Ifosfamide with Methotrexate?

MediHelp rates the interaction as major. Ifosfamide and Methotrexate can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Both agents are cytotoxic and cause myelosuppression and immunosuppression, so combination raises the risk of severe cytopenias and infection. Ifosfamide may also cause nephrotoxicity, which could delay methotrexate clearance.

How serious is the interaction between Ifosfamide and Methotrexate?

MediHelp rates it major, 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 closely, and adjust doses per the chemotherapy protocol. Provide supportive care and infection prophylaxis as indicated.

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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