S.H.
**Adding this:
About Mucus secretions- in allergy it is clear. If sick or having an infection, mucus will be yellow or green or brown.
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Fever, is NOT allergy.
It is an illness or Flu or infection.
Back to back colds, happen. It is often another type of virus, not a relapse.
My son, was sick 2 weeks ago. A head cold and sore throat and symptoms like your son. He did not have strep or anything. Then he got better. But yesterday... he got sick again. Today he is home sick from school. I took him to the Doctor. The Doctor said it is NOT a relapse and it is another cold virus. And it is not allergy.
Meanwhile, I got sick too. From him, last week. But mine progressed more... and I developed Bronchitis, for which I needed Antibiotics etc.
Per Antibiotics, if one family of Antibiotics does not work, then another type of Antibiotic needs to be used. BUT... antibiotics are generally for bacterial infections. Not viral.
IF, allergy OTC meds do not help... then the person is sick.
But allergy meds, have things in it which dries up mucus secretions. BUT if a person is sick, it will NOT clear up, completely.
Nasal sprays, are typically steroidal based. "Corticosteroid" to be specific.
Per my Pediatrician, he did not recommend this for my son. He is a child. He only recommended a Saline, nasal spray. BUT in my case, being an Adult, I was prescribed a Nasonex steroidal nasal spray.
My Pediatrician said: that per my son, it is NOT a relapse of the same cold he had 2 weeks ago. Relapses, are not common. BUT there are many cold viruses going around now, and so many different strains.
Also, per this age (my son is 5), a child typically gets sick about 8 times a year. Then from ages 7-8, the frequency of a child getting sick, lessens.
Younger kids, are very touchy and grab things and touch things and their hands/face/mouth etc. And they are not as hygenic as older kids. Thus, due to their age related habits, and them being in either Preschool or school, germs transmit very readily. But in older kids, this is less so. This is per my Doctor.
Per what OTC med to give your son: you need to ask the Pediatrician. He is only 2 years old.
Flonase or Nazonex type things, can take... up to 2 weeks to make a marked difference.
Keep that in mind.
It is not instant cure.
And it is steroidal based.
So, ask the Doctor, about how to stop, once on it.
Inhalers: do NOT "cure" the illness. What it does is to reduce the inflammation of the bronchial airways, so that the person can breathe.
Nor does it stop, mucus.
Also, per the colds that my son and I had, we also had, scratchy frog voices. Too. And so did all of the other people we know, who was sick with this cold... which is going around in my city. And the low grade fever.
But for me, I actually got Laryngitis. My son on the other hand, just had the scratchy frog voice. In addition to all the other symptoms, that you mentioned your son, has.
Secondary infections can also happen after being sick.
Like me. I got Bronchitis.
And if your son keeps getting fever... he is sick.
This is not allergy.
Maybe your son is sick... PLUS he has seasonal allergies.
Which exacerbates, your son's cold or visa versa.
But again, Fever, is not allergy.