Successful treatment of lithium toxicity with sodium polystyrene sulfonate: a retrospective cohort study

Context. Lithium (Li) is a first-line treatment for bipolar disorder but has a narrow therapeutic index. Treatment of Li toxicity includes supportive measures and hemodialysis in severe cases, but this modality is not always immediately available. Sodium polystyrene sulfonate (SPS, Kayexalate™), a cation exchanger, has been promising in animal models and human reports to reduce absorption and enhance elimination of Li. Material and methods. A retrospective cohort study was conducted. All cases of chronic Li intoxication were reviewed in two adult-care hospitals from 2000 to 2009. A group comparison and a within-patient comparison were performed to compare the effect of SPS on the median Li half-life (T1/2). For this study, at least three serum Li levels were required for T1/2 calculations. Results. Forty-eight patients met inclusion requirements, 12 of whom had taken SPS. Median Li T1/2 in the treated and control groups was 20.5 and 43.2 hours, respectively (p = 0.0006). In the 12 treated patients, Li T1/...