Citalopram serum and milk levels in mother and infant during lactation.

We present a case of intensified therapeutic drug monitoring (TDM) of citalopram in mother and newborn infant after clinically observed selective serotonin reuptake inhibitor (SSRI)-associated symptoms 2 weeks until 2 months after delivery. The SSRI-associated symptoms observed in the infant (up to 3 weeks after delivery) were irregular breathing, sleep disorders, hypotonia, and hypertonia. We conclude that the SSRI-associated symptoms in the infant represent citalopram withdrawal effects rather than side effects caused by breastfeeding. This case illustrates the importance of a flexible TDM program and a multidisciplinary approach in a hospital setting to deal with cases of drug-associated adverse effects, such as SSRI withdrawal effects.