**7. Probiotics in asthma**

Asthma, a chronic complex airway disease, is characterized by reversible airflow obstruction, bronchial hyper responsiveness, and underlying inflammation [87]. In recent decades, the prevalence of asthma has risen. One possible mechanism behind this high prevalence is the microbial hypothesis, which suggests that less microbial exposure upregulates T helper cell type-2 (Th2) cytokine development, leading to a rise in allergic diseases [75]. A meta-analysis found that while perinatal and early-life probiotic administration reduces children's risk of atopic sensitization and total rates of immunoglobulin E (IgE), it may not reduce their risk of asthma [88]. However, in addition to routine treatment, several studies have documented the advantage of using probiotics for treating children with asthma. A randomized, placebocontrolled trial for 7-week treatment with *Enterococcus faecalis* showed reduced peak flow variability in children with asthma [89]. Lee et al. have reported substantial improvements in the pulmonary function of children with asthma following a regimen of supplementation of vegetables, fish oil, and fruit along with probiotic administration. Studies, however, have shown that *Lactobacillus* is safe for children with asthma [90, 91].
