Use of losartan during pregnancy, especially after the first 3 months, can cause low blood pressure, kidney failure, too much potassium, or death in newborns. Additionally, when hydrochlorothiazide is used during pregnancy, it may cause jaundice, blood problems, and other side effects in the newborn baby. Therefore, it is important that you check with your doctor immediately if you think that you may be pregnant . It is not known whether losartan passes into breast milk. However, it does pass into the milk of lactating rats.
Hydrochlorothiazide does pass into breast milk.
Be sure that you discuss this with your doctor if you decide to breast-feed while taking these medicines. Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of losartan and hydrochlorothiazide combination in children with use in other age groups. Therefore, it may not be known whether they work exactly the same way as they do in younger adults. Although there is no specific information comparing the use of losartan and hydrochlorothiazide combination in the elderly with use in other age groups, this medicine is not expected to cause different side effects or problems in older people than it does in younger adults. Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur.