Obes Surg. 2026 Jul 15. doi: 10.1007/s11695-026-08731-0. Online ahead of print.
ABSTRACT
BACKGROUND: The pharmacokinetics of oral psychotropic drugs can change after metabolic and bariatric surgery (MBS), affecting drug exposure. Given the risk of psychiatric decompensation, patients using psychotropic medications constitute a high-risk group requiring careful post-MBS monitoring. In particular, lithium, tricyclic antidepressants (TCAs), and clozapine are of concern because of their well-established dose-effect relationships, susceptibility to MBS-related exposure changes, and suitability for therapeutic drug monitoring (TDM). This study aimed to examine the prevalence of treatment interventions related to these medications in bariatric patients to prevent drug-related problems such as under- or overexposure requiring dosage adjustments or drug discontinuation.
METHODS: In this retrospective study, patient records from January 2017 to December 2023 were reviewed. Patients who underwent MBS and were using lithium, TCAs (amitriptyline, clomipramine, dosulepin, doxepin, imipramine, maprotiline, nortriptyline), and/or clozapine were included. Baseline characteristics, treatment interventions, and available drug plasma concentrations were collected preoperatively and up to one year postoperatively.
RESULTS: A total of 163 patients were included. Psychotropic drug adjustments were observed in 27 patients (16.6%) within the first year following MBS. Both pre- and postoperative drug plasma concentrations were available for three patients (1.8%). Three patients experienced worsening of psychiatric symptoms that necessitated hospitalization or intensive monitoring. No statistically significant differences in intervention rates were observed among patients with psychiatric disorders or pain.
CONCLUSION: Although only a minority of patients required psychotropic drug treatment interventions, monitoring psychotropic drug treatment is essential for safe and effective treatment post-MBS. Greater attention is needed regarding altered drug exposure, and plasma concentration monitoring may help optimize psychotropic pharmacotherapy in these patients.
PMID:42455492 | DOI:10.1007/s11695-026-08731-0
