Bipolar disorder (BPD) is associated with high rates of suicide attempts but the anti-suicidal effect of mood stabilizing agents remains unclear. This study aimed to examine the association between mood stabilizing agents (lithium, valproate, lamotrigine, carbamazepine or antipsychotics) and risk of suicide attempts in patients with BPD using self-controlled case series study design. Among 14,087 patients with BPD who received mood stabilizing agents from 2001 to 2020 in Hong Kong, 1316 patients had at least one suicide attempts during the observation period. An increased risk of suicide attempts was observed 14 days before treatment initiation compared to non-exposed period. Following treatment initiation, an increased risk with smaller magnitude was found with the use of mood stabilizing agents. A lower risk was observed with lithium and antiepileptics while the risk remained attenuated with decreasing magnitude with antipsychotics. During 30-day post-treatment period, the risk was elevated. Therefore, this study suggests that use of mood stabilizing agents is not causally associated with an increased risk of suicide attempts. Indeed, there are potential protective effects of lithium and antiepileptics against suicide attempts. Assiduous monitoring of symptoms relapse and warning signs of suicide should be part of the management plan and discussed between clinicians, caregivers and patients., Competing Interests: Declaration of Competing Interest Esther W. Chan has received grants from Research Grants Council (RGC, Hong Kong), Research Fund Secretariat of the Food and Health Bureau, National Natural Science Fund of China, Bayer, Bristol-Myers Squibb, Pfizer, Janssen, Novartis, Amgen, AstraZeneca, Takeda, the RGA Reinsurance Company, Narcotics Division of the Security Bureau of the Hong Kong Special Administrative Region, the National Health and Medical Research Council Australia; consulting fees from AstraZeneca, Pfizer and Novartis; and honorarium from the Hospital Authority Hong Kong, outside the submitted work. Joseph F. Hayes has received consultancy fees from Wellcome Trust and juli Health.Yun Kwok Wing has received honorarium from Eisai Hong Kong and consultation fees from Eisai Co., Ltd, grants from Research Grants Council (RGC, Hong Kong). Wallis C.Y. Lau reports grant from AIR@InnoHK administered by Innovation and Technology Commission, outside the submitted work. Kenneth K.C. Man received the CW Maplethorpe Fellowship, grants from the National Institute for Health Research, United Kingdom; the European Union Horizon 2020 Framework; Hong Kong Research Grant Council and personal fees from IQVIA Holdings, Inc., unrelated to this work. Ian C.K. Wong has received grants from the Research Grants Council (RGC, Hong Kong), the National Institute for Health Research, United Kingdom, National Health and Medical Research Council in Australia, Innovative Medicines Initiative (IMI), Shire, Janssen-Cilag, Eli-Lily, Pfizer, Bayer, Bristol-Myers Squibb, Takeda, Amgen, AstraZeneca and the European Union FP7 program. He is a member of the National Institute for Health and Clinical Excellence (NICE) ADHD Guideline Group, the British Association for Psychopharmacology ADHD guideline group and an advisor to Shire. He also receives personal fee from IQVIA and Jacobson Pharmaceutical and speaker fees from Janssen and Medice in the previous 3 years. Vanessa W.S. Ng, Miriam T.Y. Leung, Edwin H.M. Lee, and David P.J. Osborn, declare no conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)