Always use this medicine exactly as your doctor has told you. Contact a doctor or pharmacist if you are unsure. Montelukast must not be used together with other medicines that contain the same active ingredient, montelukast. Montelukast should be taken even if the disease is under control, and during periods of worsening of the disease (asthma attacks). Use of Montelukast in children 6 to 14 years of age: The dose is determined by the doctor who adapts it for you or your child. The recommended dose for asthma and/or seasonal allergies is one 5 mg chewable tablet once a day. For patients with asthma , take Montelukast once daily in the evening. For patients with seasonal allergies , take Montelukast once daily as prescribed by the doctor. This medicine should be taken by mouth. 5 mg chewable tablets should be chewed before swallowing. If the chewable tablet is taken with food, it should be taken 1 hour before or 2 hours after food. Use of Montelukast in adults and adolescents over 15 years of age: The dose is determined by the doctor who adjusts it for you. The recommended dose for asthma and/or seasonal allergies is one 10 mg tablet once a day. For patients with asthma , take Montelukast once daily in the evening. For patients with seasonal allergies , take Montelukast once daily as prescribed by your doctor. This medicine should be taken by mouth. 10 mg tablets can be swallowed with a little water, and can be taken alone or with food.