The amount of Montelukast dosage needs to be based on age. Montelukast is taken orally, at the time of administration, pour the product into half a cup of warm boiled water (about 50ml) and mix it to take it quickly. Adults take 1 sachet (3g) 3 times a day; under 1 year old 1 sachet per day in 3 doses; 1-2 years old 1-2 sachets per day in 3 doses; over 2 years old 2-3 sachets per day in 3 doses. Adverse reactions to Montelukast may produce mild constipation in a few individuals. Contraindications are unclear. Precautions for the treatment of acute diarrhea, should pay attention to the correction of dehydration; allergy to the product is prohibited, allergy with caution and so on. If you have a need for medication, you should go to the hospital for a clear diagnosis and use the medication after being prescribed by a doctor, do not use the medication blindly on your own, so as not to cause adverse effects on the body.