Guidance Issued for Use of Metformin to Prevent Antipsychotic-Induced Weight Gain

MONDAY, Dec. 30, 2024 (HealthDay News) — In a guideline published online Dec. 9 in Schizophrenia Bulletin, recommendations are presented for the use of metformin to prevent antipsychotic-induced weight gain (AIWG).

Aoife Carolan, from Saint John of God Hospital in Dublin, and colleagues developed a guideline for use of metformin for prevention of AIWG, following the Appraisal of Guidelines for Research and Evaluation II instrument (AGREE II).

The authors note that the only pharmacological instrument that has demonstrated efficacy for preventing AIWG is metformin. Compared with controls, co-commencement with antipsychotic medications can reduce weight gain by 4.03 kg. The guideline for metformin use was developed for co-commencement with an antipsychotic or commencement if certain criteria are met. Strong recommendations include co-commencement of metformin with medium-risk antipsychotics in the presence of one or more cardiometabolic risk factors or in those aged 10 to 25 years, as well as commencement of metformin with any antipsychotic if a >3 percent increase in baseline body weight occurs during the first year of treatment.

“This is the first published evidence-based guideline using the AGREE II framework and GRADE methods for the use of metformin to prevent AIWG incorporating recommendations for co-commencement,” the authors write. “Implementation and evaluation of the guideline will be supported by a shared decision-making package and assessment of barriers and facilitators to implementation.”

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