RESUMO
BACKGROUND: Conclusions about the usefulness of lithium dose-prediction equations are often based on retrospective evaluations, and the paucity of prospective tests is striking. METHOD: We prospectively evaluated the safety and accuracy of a lithium-dose prediction equation in a group of 29 psychiatric patients. Predicted doses were computed and rounded to the nearest multiple of 300 mg, and the respective doses of lithium carbonate were given either two or three times a day. On Day 4 or 5 following treatment initiation, morning blood samples were collected 8 to 12 hours after administration of the last dose. Patients were monitored carefully for signs of lithium toxicity. RESULTS: All 29 subjects achieved lithium concentrations between 0.5 and 1.3 mmol/L within 5 days of beginning treatment, and no participant showed any signs of lithium toxicity. CONCLUSION: The equation may be a safe, reasonable alternative to empiric dosing.
