If you take loratadine during pregnancy, pregnant mothers should not be overly nervous and should relax themselves, the drug has no significant effect on fetal growth and development. Loratadine is a piperidine compound mainly used for the treatment of allergic rhinitis, chronic urticaria and other allergic pruritic skin diseases. Its major adverse effects include headache, drowsiness, fatigue, dry mouth, nausea, palpitations, syncope, abnormal liver function, such as mildly elevated liver function, jaundice, and elevated bilirubin. Because it is classified as Class B by the U.S. Food and Drug Administration for safe maternal use, it has no side effects that cause fetal malformations or affect fetal growth and development, and can be used safely by pregnant women throughout pregnancy.