This report describes the presentation and clinical course of a 40-year-old woman who had an emergency admission for eclampsia. During routine investigations, she was found to have profound hypercalcaemia, the cause of which was identified as milk-alkali syndrome, caused by self-medication with antacid tablets for dyspepsia. Treatment with aggressive rehydration, bisphosphonates and discontinuation of antacid tablets restored normocalcaemia. The patient made a full recovery with no long-term side-effects. Her male infant was safely delivered with no deleterious effects of exposure to high calcium concentrations in utero.