Drug Levels and Effects:

Summary of Use during Lactation:

Because absorption after topical application is very limited, occasional pyrethrins and piperonyl butoxide use is acceptable in nursing mothers. This combination is recommended by the Centers for Disease Control and Prevention for the treatment of lice infestations during lactation.[1] Extensive exposure, such as from agricultural use or malaria control might have long-term health concerns because residues can be found in breastmilk.[2] Only water-miscible cream, gel orliquidproducts should be applied to the breast because ointments may expose the infant to high levels of mineral paraffins via licking.[3]

Drug Levels:

Maternal Levels.

Pyrethrins were measured in 53 breastmilk samples from 29 mothers collected 1998 to 1999 in Basel Switzerland. Pyrethrins were detected in 42 milk samples, even in mothers from households that reported no pyrethrin use. The average pyrethrins concentration was 89 mcg/kg of fat (range undetectable [<25 mcg/kg]="" to="" 341="" mcg/kg="">

Pyrethroids (permethrin, cyfluthrin, cypermethrin and deltamethrin) were found in the breastmilk of nursing mothers in 3 South African towns. Average levels in breastmilk ranged from 8.3 to 48.4 mcg/L in the 3 towns. The source was thought to be from a dusting powder widely available and used in gardening. The dosage and route of exposure (i.e., topical, inhalation, oral) could not be determined. All milk levels were below the allowable daily limit for permethrin.[5][6]

Infant Levels.

Relevant published information was not found as of the revision date.

Effects in Breastfed Infants:

Relevant published information was not found as of the revision date.

Possible Effects on Lactation:

Relevant published information was not found as of the revision date.

Alternate Drugs to Consider:



1. Workowski KA, Berman SM. Sexually transmitted diseases treatment guidelines 2006. MMWR Recomm Rep. 2006;55 (RR-11):1-94. PMID:16888612
2. Bouwman H, Kylin H. Malaria control insecticide residues in breast milk: the need to consider infant health risks. Environ Health Perspect. 2009;117:1477-80. PMID:20019894
3. Noti A, Grob K, Biedermann M et al. Exposure of babies to C(15)-C(45) mineral paraffins from human milk and breast salves. Regul Toxicol Pharmacol. 2003;38:317-25. PMID:14623482
4. Zehringer M , Herrmann A. Analysis of polychlorinated biphenyls, pyrethroid insecticides and fragrances in human milk using a laminar cup liner in the GC injector. Eur Food Res Technol. 2001;212:247-51.
5. Sereda B, Bouwman H, Kylin H. Comparing water, bovine milk, and indoor residual spraying as possible sources of DDT and pyrethroid residues in breast milk. J Toxicol Environ Health A. 2009;72:842-51. PMID:19557612
6. Bouwman H, Sereda B, Meinhardt HM. Simultaneous presence of DDT and pyrethroid residues in human breast milk from a malaria endemic area in South Africa. Environ Pollut. 2006;144:902-17. PMID:16564119

Substance Identification:

Substance Name:


CAS Registry Number:


Drug Class:

  • Antiinfective Agents

  • Antiparasitic Agents

  • Insecticides

  • Administrative Information:

    LactMed Record Number:


    Last Revision Date:

    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.