TY - JOUR T1 - Overdrinking-induced hyponatraemia in the 2007 London Marathon JF - BMJ Case Reports DO - 10.1136/bcr.09.2008.1002 VL - 2009 SP - bcr0920081002 AU - Stephen B Draper AU - Kate J Mori AU - Simon Lloyd-Owen AU - Timothy Noakes Y1 - 2009/01/01 UR - http://casereports.bmj.com/content/2009/bcr.09.2008.1002.abstract N2 - We report a case of overdrinking-induced hyponatraemia from the 2007 London Marathon. The patient was a 37-year-old experienced female marathon runner. She was brought to the emergency room more than 6 h after completing the marathon suffering from diarrhoea, vomiting and confusion, and was unable to recall any detail of the race. An arterial blood sample confirmed hyponatraemia ([Na+] 117 mmol.l−1) associated with hypokalaemia (serum potassium concentration 3.4 mmol.l−1) and respiratory alkalosis (pH 7.62, bicarbonate 16.1 mmol.l−1 and Pco2 2.14 kPa). A diagnosis of uncomplicated exercise-associated hyponatraemia due to voluntary overdrinking was made and the patient was catherised and treated with a slow (1 h) intra-venous infusion of 500 ml of 1.8% sodium chloride (NaCl) solution. The following morning her serum [Na+] had normalised at 135 mmol.l−1 and she was discharged in the afternoon. She has recovered fully without sequelae. ER -