Hello @chidanand, welcome to Connect. You mentioned your daughter was observed, does this mean some testing was done to determine it is not seasonal? If you are comfortable sharing, what sort of testing was done? Here is what Mayo Clinic has to say about allergic rhinitis, how it is diagnosed and how it is treated, https://www.mayoclinic.org/departments-centers/allergic-diseases/minnesota/overview/specialty-groups/allergic-rhinitis.
"Allergy and immunology specialists perform a comprehensive evaluation including environmental history and physical. This will include reviewing of outside information provided by the patient. Typically, allergen skin prick testing and rhinoscopy (viewing of the nasal passages, sinuses and upper airway) are also performed."
From what I was able to find, allergic rhinitis can also be referred to as hay fever. Here is additional information to the above info, https://www.mayoclinic.org/diseases-conditions/hay-fever/diagnosis-treatment/drc-20373045.
Of note, "Montelukast can cause headaches. In rare cases, it has been linked to psychological reactions such as agitation, aggression, hallucinations, depression and suicidal thinking."
@chidanand, are the medications your daughter are on helping at all?