Drug interactions
Cyclophosphamide + Mechlorethamine
Severity: Major
Cyclophosphamide and Mechlorethamine: 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 are nitrogen mustard alkylating agents, and combined use adds to bone marrow suppression and immunosuppression. This raises the risk of severe cytopenias and infection.
What this interaction means in plain words
Cyclophosphamide and Mechlorethamine 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.
Cyclophosphamide belongs to Oncology; Mechlorethamine belongs to Oncology.
Why it happens
Additive pharmacodynamic myelosuppressive and immunosuppressive effects of two alkylating agents.
What to do
Avoid duplicating alkylator therapy unless part of an established regimen. Monitor complete blood counts frequently and adjust doses for cytopenias.
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?
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Other interactions of Cyclophosphamide
Other interactions of Mechlorethamine
Frequently asked questions
Can I take Cyclophosphamide with Mechlorethamine?
MediHelp rates the interaction as major. Cyclophosphamide and Mechlorethamine 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 are nitrogen mustard alkylating agents, and combined use adds to bone marrow suppression and immunosuppression. This raises the risk of severe cytopenias and infection.
How serious is the interaction between Cyclophosphamide and Mechlorethamine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid duplicating alkylator therapy unless part of an established regimen. Monitor complete blood counts frequently and adjust doses for cytopenias.
What other medicines interact with Cyclophosphamide?
MediHelp also lists interactions of Cyclophosphamide with, for example, Adenovirus types 4 and 7 live, Belatacept, Bendamustine. The full list is on the Cyclophosphamide page.
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