Blood in the stool in children taking Montelukast Sodium Chewable Tablets may be an adverse reaction to the medication, it is recommended to suspend taking the medication and go to the hospital for examination. Montelukast Sodium Chewable Tablets are mainly used for the prevention and long-term treatment of asthma in children aged 2 to 14 years, and to reduce the symptoms of allergic rhinitis. Adverse reactions such as headache, upper respiratory tract infection, increased bleeding tendency, diarrhea, dyspepsia, dizziness, and vomiting may occur when taking Montelukast Sodium. Therefore, blood in the stool after taking the drug may be caused by the adverse reaction of the drug, if the symptoms are mild, there is no need to stop taking the drug; if the symptoms are more serious, it is recommended to suspend taking the drug and go to the hospital for examination. Montelukast Sodium Chewable Tablets should be used in strict accordance with medical advice, and is contraindicated for those who are allergic to any of the ingredients in this product.