Clinical pharmacy activities specific to patients treated with lithium.

Objectives: Medication compliance in lithium-treated patients is poor (43-46%) and may be responsible for relapse or toxicity. Improving understanding of treatment principles leads to increased medication adherence. To do this, targeted and personalised pharmaceutical interviews on lithium were developed and implemented by a clinical pharmacy team in adult psychiatric departments of the Lille university hospital center. The primary aim of this work was to assess medication adherence with lithium, patients' understanding of the drug and of potential adverse effects. A secondary objective was to evaluate the feasibility of these pharmaceutical interviews in practice.

Methods: Implementation of self-assessment questionnaires measuring medication adherence (Medication Adherence Rating Scale) as well as knowledge of lithium and risk of exposure to toxic effects (Lithium Knowledge Test) of patients. Conducting targeted pharmaceutical interviews about lithium, and recording of time spent, satisfaction of medical teams and difficulties encountered.

Results: Twenty patients were included in the 6-month study. Every patient benefited from a personalized pharmaceutical interview by a pharmacy intern focused on lithium during his hospitalization. Lithium adherence, patient knowledge and risk exposure to lithium toxicity was 5.5±0.9 (target ≥8), 8.9±0.9 (target >6) and 4.0±0.5 (target <4). The median time required for these new activities was 95minutes per patient. Medical satisfaction was observed in 70% to 100% of cases depending on the criterion assessed. The lack of pharmaceutical time and communication difficulties were the main obstacles encountered.

Conclusion: Medication compliance in patients treated with lithium is poor as described in the literature. To improve this and to optimise drug management, patients have benefited from targeted and personalised pharmaceutical interviews. The satisfaction of patients and the medical team made it possible to sustain these new pharmaceutical activities.