Therapeutic effects of probiotics on symptoms of irritability/emotional lability associated with neurodevelopmental conditions: a systematic review and meta-analysis of placebo-controlled trials

Ping-Wen Huang; Chen Chia-Min; Cheuk-Kwan Sun; Yu-Shian Cheng; Yen-Hsiang Tang; Cheng Liu; Kuo-Chuan Hung

doi:10.1016/j.ctim.2025.103132

Therapeutic effects of probiotics on symptoms of irritability/emotional lability associated with neurodevelopmental conditions: a systematic review and meta-analysis of placebo-controlled trials

Complement Ther Med. 2025 Jan 24:103132. doi: 10.1016/j.ctim.2025.103132. Online ahead of print.

Authors

Ping-Wen Huang¹, Chen Chia-Min², Cheuk-Kwan Sun³, Yu-Shian Cheng⁴, Yen-Hsiang Tang⁵, Cheng Liu⁶, Kuo-Chuan Hung⁷

Affiliations

¹ Department of Emergency Medicine, Show Chwan Memorial Hospital, Changhua City, Taiwan.
² Department of Natural Biotechnology, Nanhua University, Chiayi, Taiwan.
³ Department of Emergency Medicine, E-Da Dachang Hospital, I-Shou University, Kaohsiung City, Taiwan; School of Medicine, College of Medicine, I-Shou University, Kaohsiung City, Taiwan.
⁴ Department of Psychiatry, Tsyr-Huey Mental Hospital, Kaohsiung Jen-Ai's Home, Taiwan.
⁵ Department of Critical Care Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Department of Medicine, MacKay Medical College, New Taipei City, Taiwan.
⁶ Department of Physical Education, Huazhong University of Science and Technology, Wuhan 430074, China.
⁷ Department of Anesthesiology, Chi Mei Medical Center, Tainan City, Taiwan. Electronic address: ed102605@gmail.com.

PMID: 39864755
DOI: 10.1016/j.ctim.2025.103132

Abstract

Objectives: The current study aimed at investigating the efficacies of probiotics in alleviating the symptoms of irritability/emotional lability in individuals with a neurodevelopmental condition.

Methods: Randomized placebo-controlled trials were identified through searching major electronic databases from inception to December, 2023. The outcome of interests included improvements in the symptoms of irritability/emotional lability. Outcomes were quantitatively expressed as effect size (ES) based on standardized mean difference (SMD) with 95% confidence interval (CI).

Results: Seven studies with 1479 participants were included in this meta-analysis. The primary results revealed a significant improvement in the symptoms of irritability/emotional lability in individuals with neurodevelopmental conditions receiving probiotics compared with the placebos (SMD= -0.17, p=0.03). Subgroup analyses demonstrated an association between a significant improvement in the symptoms of irritability/emotional lability and the use probiotics relative to placebos only in studies using multiple-strain probiotics (SMD=-0.19, p=0.04, three studies with 452 participant) but not in those adopting single-strain regimens.

Conclusions: Our study supported the use of probiotics for alleviating the symptoms of irritability/emotional lability in individuals with neurodevelopmental conditions, mainly in those receiving multiple-strain probiotics as supplements. Nevertheless, the limited number of studies targeting irritability as their primary outcomes, and most did not investigate other confounding factors such as dietary habits or consumption of other nutritional supplements may impair the robustness of evidence. Our results, which were derived from a limited number of available trials, warrant further large-scale clinical investigations for verification.

Keywords: and meta-analysis; children/adolescent; irritability; probiotics.

Publication types

Review