A 12-year retrospective review of neonates admitted with hypernatraemic dehydration to the neonatal unit of the University Hospital of the West Indies was conducted between 1 January 1990 and 31 December 2001. Twenty-four infants fulfilled the criteria for hypernatraemic dehydration. Nineteen (79%) women were either nulliparous or primiparous with a mean (SD) age of 26.9 (4.4) yrs. Modal length of hospital stay for mothers was 24 hrs. Twenty (83.3%) infants were exclusively breastfed. Mean (SD) age at presentation was 7.4 (3.8) days. Mean (SD) percentage weight loss between birth and presentation was 18.9% (6.3). Mean (SD) serum sodium at presentation was 164.8 (13.9) mmol/L. Babies visited at home by nurses had a lower mean serum sodium, were less dehydrated and were significantly less acidiotic. Their mean (SD) length of hospital stay was also significantly less [4.2 (1.4) days] than those who were not visited [7.9 (3.8) days] (p < 0.05). Complications occurred in 19 (79%) of infants and included renal failure (19, 79%), seizures (3, 13%) and intraventricular haemorrhage (1, 4%), and one died (4%). Hypernatraemic dehydration is an uncommon complication of failure to establish breastfeeding but is associated with severe morbidity and mortality. Education programmes are needed to increase awareness amongst health-care workers and mothers in order to prevent the problem. PMID: 15720886 [PubMed - indexed for MEDLINE