Hello, Thank you for asking at HCM. I went through your query and would like to make suggestions for him as follows: 1. It would be best if he is examined by an ENT specialist because common causes of such complaints are allergic rhinitis, sinusitis, chronic pharyngitis, etc. 2. Singulair (Montelukast) is not an antihistamine. I would suggest him to add an antihistamine (like fexofenadine, cetirizine, levocetirizine, etc) to montelukast, which might work better. 3. Regular care of nose and throat like regular steam inhalation (for nose symptoms) and regular warm saline gargles (for throat symptoms) will be helpful to him. 4. In general, I would suggest him to avoid exposure to dusts, smokes and air pollution as much as possible. 5. I would also suggest him to take adequate fluids during day to maintain hydration and a healthy diet rich in vitamins, minerals and antioxidants for overall health. Hope above suggestions will be helpful to him. Should you have any further query, please feel free to ask at HCM. Wish him the best of the health ahead. I appreciate your concern for your student and asking on his behalf. Thank you & Regards.