Use of anti-infective agents during lactation: Part 2--Aminoglycosides, macrolides, quinolones, sulfonamides, trimethoprim, tetracyclines, chloramphenicol, clindamycin, and metronidazole

Determination of levofloxacin by HPLC with fluorescence detection in human breast milk

Aim: A new HPLC method with fluorescence detection has been developed and validated for the determination of levofloxacin, one of the fluoroquinolone class antibiotics, in breast milk. Materials & methods: Chromatographic separation was carried out on a reversed phase C18 column with acetonitrile and 10 mM o-phosphoric acid (25:75, v/v) mobile phase composition. Moxifloxacin was used as internal standard and the peaks were detected by fluorescence detection. Results & conclusion: Calibration graph was found linearly within the range of 2.5-500 ng/ml. Limit of detection and limit of quantification were found to be 0.63 and 2.11 ng/ml, respectively. Mean absolute recovery was 96.18%. The developed method has been successfully applied to the determination of levofloxacin in human breast milk taken from two healthy volunteers.

Antibiotics and lactation: An overview of relative infant doses and a systematic assessment of clinical studies

Breastfeeding is important for the development of the child. Many antibiotics are considered safe during breastfeeding. The aim of the study was to assess the quality of lactation studies with antibiotics using the FDA and International Lactation Consultant Association quality guidelines for lactation studies. The secondary goal was to determine the exposure of the breastfed infant to antibiotics in relation to bacterial resistance and the developing microbiome. A literature search was performed and the included studies were scored on methodology, parameters concerning maternal exposure to antibiotics, maternal plasma and milk sampling. The infant exposure has been calculated and expressed as a percentage of a normal infant therapeutic dose. Sixty-six studies were included in five antibiotic groups (broad-spectrum penicillin, cephalosporins, macrolides and lincosamides, quinolones and sulphonamides). Cephalosporins were the most studied group of antibiotics (n = 21). Fifteen studies met all the criteria of "mother exposure to antibiotic". Six studies met every criterion related to "plasma sampling". Only one case report met all listed criteria for lactation studies. The correct calculation of infant exposure to antibiotics via the milk:plasma ratio (AUC) varies between 13% for macrolides and 38% for broad-spectrum penicillin. The highest assessed exposure as a percentage of infant therapeutic dose was for metronidazole (11%). The studies meet to a limited extent with the quality standards for lactation research. The breastfed infants are exposed to a subtherapeutic concentration of antibiotics.

Antibiotics and Breastfeeding

During the breastfeeding period, bacterial infections can occur in the nursing mother, requiring the use of antibiotics. A lack of accurate information may lead health care professionals and mothers to suspend breastfeeding, which may be unnecessary. This article provides information on the main antibiotics that are appropriate for clinical use and the interference of these antibiotics with the infant to support medical decisions regarding the discontinuation of breastfeeding. We aim to provide information on the pharmacokinetic factors that interfere with the passage of antibiotics into breast milk and the toxicological implications of absorption by the infant. Publications related to the 20 most frequently employed antibiotics and their transfer into breast milk were evaluated. The results demonstrate that most antibiotics in clinical use are considered suitable during breastfeeding; however, the pharmacokinetic profile of each drug must be observed to ensure the resolution of the maternal infection and the safety of the infant.

Excretion of antimicrobials used to treat methicillin-resistant Staphylococcus aureus infections during lactation: safety in breastfeeding infants

Community-acquired strains of methicillin-resistant Staphylococcus aureus (MRSA) have become a common cause of skin and soft tissue infections in the United States. These infections sometimes require treatment with antibiotics, and with the increasing resistance of pathogens to these agents, choosing the appropriate drug can be difficult. In lactating women who develop these infections, selecting an antibiotic is even more challenging, as clinicians need to be aware of risks to the infant from the drug excreted during lactation. To our knowledge, no review has addressed the safety of antibiotics in breastfeeding infants when the drugs are used to treat maternal skin and soft tissue infections from MRSA. Thus, we performed a literature search of the PubMed-MEDLINE and EMBASE databases (1974-March 2009), reviewed reference citations from identified publications, researched antibiotic prescribing information, and corresponded with drug manufacturers. Case reports, case series, and both in vivo and in vitro clinical trials were evaluated for the following antibiotics: clindamycin, daptomycin, linezolid, quinupristin-dalfopristin, rifampin, tetracycline, doxycycline, minocycline, tigecycline, trimethoprim-sulfamethoxazole, and vancomycin. Information for the newer antibiotics (linezolid, quinupristin-dalfopristin, tigecycline, and daptomycin) was limited. Despite heterogeneity in the data for the older antibiotics (clindamycin, rifampin, tetracyclines, trimethoprim-sulfamethoxazole, and vancomycin), all appear to be relatively safe in the minimal quantities nursing infants ingest through breast milk. Although the risk to infants seems to be relatively low for most of the agents we explored, the paucity of data indicates a need for close monitoring of breastfed infants whose mothers are receiving an antibiotic for an MRSA skin and soft tissue infection.

Breast-feeding in a woman with cystic fibrosis undergoing antibiotic intravenous treatment

We report the case of a 30-year-old woman with cystic fibrosis (CF) chronically infected with Pseudomonas aeruginosa who delivered and breast-fed a healthy boy. While breast-feeding the woman had to undergo an i.v. antibiotic course with tobramycin, due to pulmonary exacerbation. Tobramycin was not detected in her milk and lactation could be continued. This is the first time that the presence of tobramycin in the milk of a CF woman during i.v. administration has been investigated.