You have taken treatment for allergic breathing problem, and later developed fever
.But fever can not be due to side effect of any tablet usually given for allergic breathing problems.
I would suggest you to record temperature pattern and then consult doctor
. There are many conditions like TB/Malaria
where particular temperature rise pattern will be present.
Get lung function test [PFT] and imaging too ,to rule out infective foci.
As fever is there means , there is infective foci in body.
So consult doctor for thorough clinical examination.