May 22 2022


Risks to the infant

The possible influence of amoxicillin associated with clavulanic acid on breastfeeding has not been evaluated extensively in the scientific literature. It is available a study of a small number of cases that does not shows a significant increase in adverse reactions in infants exposed to antibiotics through breast milk, although the number of cases of the study have been very few (n = 14).

A prospective study on mothers that called by telephone to an information service about adverse reactions in their infants while receiving cefuroxime (n = 38) or amoxicillin / clavulanate (n = 67) showed , a significant increase of adverse reactions in these latter infants (22.3%) compared to the control group of infants (n = 40) exposed to amoxicillin (7.5%, P = 0.046, RR = 2.99, 95% CI 0.92-9.68 ). The reactions to beta-lactamic associated with clavulanic acid consisted of rash (5.9%), agitation (8.9%), diarrhea (5.9%), constipation (1.5%) and, in one case, a transient and moderate increase of transaminases.

Influence on lactation

Amoxicillin in milk reaches its maximum concentration at 4-5 hours after the intake. With a standard dose to the mother (1.500 mg), an exclusively breastfed infant would receive, according to estimates based on the concentration of breast milk, a dose of 0.25 to 0.5% of that used for the treatment of an infection of the infant itself.

No data are available on the passage of clavulanic acid into breast milk.


This medication is considered compatible with breastfeeding. There are some reports of rare cases of agitation, rash and diarrhea in infants, coincident with the administration of amoxicillin/clavulanic acid to the mother. If presents any adverse reaction as described, should be monitored the evolution of the infant .


1.Benyamini L, Merlob P, Stahl B et al. The safety of amoxicillin/clavulanic acid and cefuroxime during lactation. Ther Drug Monit. 2005;27:499-502.
2.Campbell AC, McElnay JC, Passmore CM. The excretion of ampicillin in breast milk and its effect on the suckling infant. Br J Clin Pharmacol. 1991;31:230p.
3.Chung AM, Reed MD, Blumer JL. Antibiotics and breast-feeding: a critical review of the literature. Pediatr Drugs 2002;4:817-37.
4.Ito S, Blajchman A, Stephenson M et al. Prospective follow-up of adverse reactions in breast-fed infants exposed to maternal medication. Am J Obstet Gynecol. 1993;168:1393-9.
5.Kafetzis DA, Siafas CA, Georgakopoulos PA et al. Passage of cephalosporins and amoxicillin into the breast milk. Acta Paediatr Scand. 1981;70:285-8.
6. Matheson I, Samseth M, Loberg R, Faegri A, Prentice A. Milk transfer of phenoxy-methylpenicillin during puerperal mastitis. Br J Clin Pharmacol 1988;25(1):33-40.
7.Mathew JL. Effect of maternal antibiotics on breast feeding infants.Postgrad Med J. 2004 Apr;80(942):196-200.
8.Vorherr H. Drug excretion in breast milk. Postgrad Med 1974;56:97-104.

Warning of the manufacturer:

This medicine may be used during lactation. There is not produced any adverse effect in the infant, except the potential risk of sensitization due to the presence of traces of the association of both drugs in breast milk. It may occur mucosal colonization by yeasts and diarrhea in infants.