Help me to get out of this

Patient: I am having cough more than 3 months.. Had cold and flu first.. Doctor prescribed me the normal cold flu medication.. Afterwards he prescribed medication saying I am having throat infection… But symptoms won’t go away.. . I have cough with phlegm which is white in colour.. I always need to clear my throat by gargling.. it enable sort of relief but after 2-3 days again required to clear phlegm from my threat.. so I went to throat specialist.. He given me relent tablet and told me to do the test like AEC.. I found everything normal except eiosinophilic count.. It is 7%. Then doctor prescribed me hatrazan tablet for 21 days.. It’s been 2 days now but my throat started to itch very intensively and also nose stared to running constantly and producing phlegm more than before… I am having this phlegm and cough in the evening to night… it does not bother me in sleep… Is this because of hatrazan? Is it allergy or some else… I feel wheezing in my chest and it goes away after clearing my throat…. please help me…

Symptoms: Cough with phlegm, post nasal drip, throat swelling and itching