Can allergies cause cold-like symptoms?

[OonaLoona2]

DS is 3.8 years.
Since about 5 months of age he has had a cold! I know young children are more susceptible to colds and it's common for them to have lots but he really does have cold symptoms all the time.
Occasionally there will be a day or two symptom free but then it will start again. Symptoms always come on very suddenly, starting with lots of sneezing then within an hour or two his nose is blocked/running with thick green mucous and he's coughing - often enough to make him sick.
His colds also never seem to spread to anyone else in the house (myself , dh and 3 other dc) which is unusual.
After another bad night of him coughing so hard he can't catch his breath and wheezing, breathing very fast and a trip to out of hours dr (only to be told that it's 'just a cold') I'm wondering if he isn't actually suffering colds but has an allergy to something.
Is it likely?

[Gileswithachainsaw]

Dd was permanently congested as a baby went away as soon as she was on the prescription milk.

Prior to that she had gunky eyes and had to have nose sprayed out several times a night.

Is there a history of asthma In the family?

[OonaLoona2]

Points I should probably add, but don't actually know if they're relevant:
We don't have any pets indoors and he doesn't really interact with the ones outside.
He was breast fed, baby led weaned at about 5 months which is when the 'colds' started.
He has no skin problems - eczema, rashes etc.
He is and has always been a good weight/size for his age and has grown steadily according to percentile charts.

[OonaLoona2]

Oldest dd has asthma.

[Gileswithachainsaw]

It might be worth starting a food diary. That might enable you to see if it's worse after a particular food or not.

Sounds as if there could be a need for an inhaler if he can't sleep and is struggling to breathe and is wheezy etc so I'd make an appointment with a dr you trust and isn't so dismissive.

Might also be worth seeing if an antihistamine helps on the bad days

[user1471537877]

I was like this as a baby, child and into my teens when it was found I had an allergy to house dust mites which was causing chronic allergic rhinitis

3 days after starting a nose spray I was a different child!

In a baby I would suggest trying an appropriate anti histamine for a couple of weeks to see if they settle

Try damp dusting their room and look at advice on putting pillows and soft toys in the freezer to kill off the mites

You can also get allergy covers for pillows and duvets

[vvviola]

When DD2 had small exposures to dairy (she's allergic and larger exposures meant eczema and hives) she would often get a runny nose and coughing and wheezing. Her allergy didn't present until she was weaning (breastfed before then, and afterwards as she wouldn't take the dairy free formula).

It might be worth keeping a food diary to see if it is particularly bad at any time.

(She also had massive black bags under her eyes that also cleared up when we eliminated dairy from her and my diet - even though her sleep didn't really improve)