Losartan potassium was not carcinogenic when administered at maximally tolerated dosages to rats and mice for 105 and 92 weeks, respectively. Losartan potassium was negative in the microbial mutagenesis and V-79 mammalian cell mutagenesis assays and in the in vitro alkaline elution and in vitro and in vivo chromosomal aberration assays. In addition, the active metabolite showed no evidence of genotoxicity in the microbial mutagenesis , in vitro alkaline elution, and in vitro chromosomal aberration assays. The NTP, however, found equivocal evidence for hepatocarcinogenicity in male mice. It is not known whether losartan is excreted in human milk, but significant levels of losartan and its active metabolite were shown to be present in rat milk.
Thiazides appear in human milk.
Because of the potential for adverse effects on the nursing infant, a decision should be made whether to discontinue nursing or discontinue the drug , taking into account the importance of the drug to the mother. Pediatric Use Safety and effectiveness in pediatric patients have not been established. No overall differences in effectiveness or safety were observed between these patients and younger patients, but greater sensitivity of some older individuals cannot be ruled out.