Cyclophosphamide use while Breastfeeding
Drugs containing Cyclophosphamide: Cytoxan, Cytoxan Lyophilized, Neosar
Cyclophosphamide Levels and Effects while Breastfeeding
Summary of Use during Lactation
Most sources consider breastfeeding to be contraindicated during maternal antineoplastic drug therapy.
Drug Levels
Maternal Levels. Unmetabolized cyclophosphamide has been qualitatively detected in milk 1, 3, 5 and 6 hours after an intravenous injection of 500 mg of drug in one patient.[1][2] Quantitative determination has not been reported.
Infant Levels. Relevant published information was not found as of the revision date.
Effects in Breastfed Infants
In one 23-day-old infant, neutropenia, thrombocytopenia and a low hemoglobin were possibly caused by cyclophosphamide after 3 days of maternal treatment with cyclophosphamide 6 mg/kg intravenously daily (total dose 300 mg).[3]
In a 4-month-old, neutropenia was probably caused by cyclophosphamide in a mother 9 days after the last of 6 weekly doses of 800 mg cyclophosphamide intravenously, 2 mg vincristine intravenously and daily doses of 30 mg of prednisolone orally. Neutropenia persisted at least 12 days and was accompanied by a brief episode of diarrhea.[4]
Possible Effects on Lactation
Relevant published information was not found as of the revision date.
Alternate Drugs to Consider
Dependent on the condition being treated.
References
1. Duncan JH, Colvin OM, Fenselau C. Mass spectrometric study of the distribution of cyclophosphamide in humans. Toxicol Appl Pharmacol. 1973;24:317-23. PMID: 4741053
2. Wiernik PH, Duncan JH. Cyclophosphamide in human milk. Lancet. 1971;1(7705):912. PMID: 4102054
3. Durodola JI. Administration of cyclophosphamide during late pregnancy and early lactation: a case report. J Nat Med Assoc. 1979;71:165-6. PMID: 423292
4. Amato D, Niblett JS. Neutropenia from cyclophosphamide in breast milk. Med J Aust. 1977;1:383-4. PMID: 859486
Cyclophosphamide Identification
Substance Name
CAS Registry Number
6055-19-2
Drug Class
- Antineoplastic Agents
Administrative Information
LactMed Record Number
77
Information from the National Library of Medicine's LactMed Database.
Last Revision Date
2010-11-01
Disclaimer
Information presented in this database is not meant as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. The U.S. government does not warrant or assume any liability or responsibility for the accuracy or completeness of the information on this Site.
See Also...
- Cyclophosphamide use during Pregnancy
- Cyclophosphamide Consumer Information
- Breastfeeding Support Group
- Safe Medications during Breastfeeding
- Medicine use while Breastfeeding
- Medicine use during Pregnancy
Disclaimer: This information is not intended as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. Use of this website signifies your agreement to the Terms of Use and Online Privacy Policy.


