Hello, Thank you for asking at HCM. I would like to make suggestions for your son as follows: 1. It is good that he does not require any inhaler or medication at present. 2. I would suggest you to take rescue inhalers (salbutamol), antihistamines (cetirizine/levocetirizine/fexofenadine), montelukast and oral corticosteroids (prednisolone) with you. 3. Please see your pediatrician before starting for Leh-Ladakh. Please ask him for action plan for asthma symptoms - how to recognize an asthma attack, which drugs to be used, when to be used and what should be the dosage. 4. Going to Leh-Ladakh can make effects on your child s health in multiple ways: a. Low oxygen levels generally would not cause problem to a normal 11 year boy, but should he have an attack of asthma, low oxygen concentration could make the attack more severe. b. Change in environment and exposure to cold air are potential triggers for asthma attacks. c. A rapid ascent to high altitude can cause changes in lung physiology and may precipitate pulmonary edema (in any normal individual, no relation with asthma). Symptoms of pulmonary edema should be differentiated from those of an asthma attack. 5. You can observe following precautions: a. Plan a gradual ascent by making frequent halts while traveling. You may plan a night-stay while ascent in between so that all the persons can acclimatize. b. Avoid exposure to dry, cold air currents. Covering ears, nose and mouth openings with think warm clothes would do this. Hope above suggestions will be helpful to you. Should you have any further query, please feel free to ask at HCM. Wish your son and family a happy and healthy travel. Happy journey. :-) Thank you & Regards.