Sulfadoxine and Pyrimethamine

Drug Levels and Effects:

Summary of Use during Lactation:

Because there is little published experience withsulfadoxineduring breastfeeding, an alternate drug may be preferred, especially while nursing a newborn or preterm infant. The manufacturer states that the combination ofsulfadoxine-pyrimethamineis contraindicated for prophylaxis during nursing and in children under 2 months of age. However, some authors have found no contraindication to the use ofsulfadoxine-pyrimethamineduring breastfeeding.[1][2]

Sulfadoxine-pyrimethamineprophylaxis of the mother should be discontinued at the first appearance in the infant of jaundice, skin rash, if a significant reduction in the count of any formed blood elements is noted, or upon the occurrence of active bacterial or fungal infections.

Drug Levels:

Maternal Levels.

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

Pyrimethaminemilk levels have been reported to range from 0.2 to 0.26 mcg/L 6 hours after a doses of 25, 50 or 75 mg in 6 women. Milk levels ranged from 0.125 to 0.155 mcg/L 24 hours after the dose and 0.095 to 0.0105 mcg/L at 48 hours.[3][4]

Three women were given a single dose ofpyrimethamine12.5 mg orally 2 to 5 days postpartum. Milk samples were obtained periodically for about 9 days after the dose. Assuming a daily intake of 1 L of milk, the infants would receive 0.14, 0.21 and 0.34 mg in milk over the study period. These values equate to an average of 46% of the maternal weight-adjusted dosage.[5]

Infant Levels.

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

Effects in Breastfed Infants:

Administration ofpyrimethamineto mothers of 26 predominantly breastfed infants 2 to 6 months old who were infected with malaria was curative in the infants.[4] The regimen consisted of 75 mg followed by a subsequent dose of 50-75 mg 4 to 7 days later. The efficacy apparently is related to breastfeeding habits, because infants in another tribal group who breastfed their infants less extensively were not protected.[3] An additional case report indicates that a maternal dose of 75 mg orally followed by 25 mg weekly cured malaria in her infant and protected her breastfed infant against becoming infected with malaria for 6 months.[5] No adverse effects were reported in any of the infants.

A study of women with HIV infection being treated for presumptive malaria included 12 nursing mothers who were taking thesulfadoxine-pyrimethaminecombination. The drug combination appeared to reduce breastmilk viral load less than chloroquine treatment. No mention was made of the effects in breastfed infants.[6]

Possible Effects on Lactation:

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

Alternate Drugs to Consider:



1. Peters PJ, Thigpen MC, Parise ME, Newman RD. Safety and toxicity ofsulfadoxine/pyrimethamine: implications for malaria prevention in pregnancy using intermittent preventive treatment. Drug Saf. 2007;30:481-501. PMID:17536875
2. Chattopadhyay R, Mahajan B, Kumar S. Assessment of safety of the major antimalarial drugs. Expert Opin Drug Saf. 2007;6:505-21. PMID:17877439
3. Clyde DF. An examination of factors involved in the transfer ofpyrimethaminein human milk. East Afr Med J. 1957;34:81-5. PMID:13437933
4. Clyde DF, Press J, Shute GT. Transfer ofpyrimethaminein human milk. J Trop Med Hyg. 1956;59:277-84. PMID:13385913
5. Clyde DF. Prolonged malaria prophylaxis throughpyrimethaminein mothers' milk. East Afr Med J. 1960;37:659-60. PMID:13694157
6. Semrau K, Kuhn L, Kasonde P et al. Impact of chloroquine on viral load in breast milk. Trop Med Int Health. 2006;11:800-3. PMID:16772000

Substance Identification:

Substance Name:


CAS Registry Number:


Drug Class:

  • Anti-Infective Agents

  • Antimalarials

  • Sulfonamides

  • Administrative Information:

    LactMed Record Number:


    Last Revision Date:

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