Hello, The symptoms looks like nasal allergy. The definitive treatment of the condition is to avoid allergic agent. If in spite of this the symptoms persists then you will need tablets like what you are taking for short term and nasal spray for long term control. How to identify the allergic agent is a common doubt. Start a diary and note every episode of allergy with place , time, date, any specific activity etc and this will give an idea of the allergic agent and the try to avoid it.

U need to get some labs done. Nasal spray can do wonders.