How to Tell the Difference Between a Common Cold and Allergies in Children

The common cold and allergies can affect anyone—especially children. Although they may cause similar symptoms, they are two different conditions and require different treatments. So, if your child is constantly sneezing and has a runny nose, how can you tell whether it’s a cold or an allergy?

The flu or common cold is caused by a viral infection, while allergies are an immune system response to allergens such as dust, pet dander, pollen, or dust mites. Despite being different, both affect the respiratory system and may cause overlapping symptoms.

If your child is sneezing, has a runny nose, a cough, and a sore throat, it's important to identify the underlying cause, as that determines the appropriate treatment. The wrong treatment could worsen their condition instead of helping them recover.

If you're unsure, the following points—based on information from Healthline—can help you distinguish between a cold and allergies.

🩺 Watch the Symptoms Carefully

Both colds and allergies cause sneezing, a runny nose, and a sore throat. However, there are several differences to observe:

🔥 Fever

Common colds often cause a mild fever.
Allergies do not cause fever.
This is because the virus triggers infection and inflammation, usually causing fever for 3–4 days in children.

💧 Mucus Changes

In a cold, mucus may start clear, then turn yellow or green and become thicker after 3–5 days.
With allergies, the mucus remains clear and watery throughout.

💢 Muscle Aches

Colds can cause muscle and joint pain, especially when severe.
Allergies do not cause body aches.

👁️ Itchy Eyes

Itchy, watery eyes are not typical with a cold.
They are very common with allergies. Children may also have puffy, dark circles around their eyes from rubbing them often.

🌬️ Reaction to Triggers

Allergy symptoms tend to worsen when exposed to triggers like air pollution, poor indoor air quality, pets, or certain foods.
A cold is not affected by these environmental factors.

⏳ How Long Do Symptoms Last? Are They Contagious?

A common cold usually goes away within 7 to 14 days, especially in winter or after exposure to cold air.
Allergy symptoms may last weeks or even months if the child continues to be exposed to the trigger.

Also:

Allergies are not contagious, since they are caused by an overreaction of the immune system to harmless substances.
In contrast, colds are highly contagious—if someone around your child is sick, they are at high risk of catching it too.

🧑‍⚕️ Consult a Doctor if Necessary

Once you determine whether it’s a cold or an allergy, you can choose the right medication:

Cold medications (like fever reducers or saline sprays) are widely available over the counter.
Allergies are treated with antihistamines and decongestants.

If you’re still not sure or your child’s symptoms don’t improve, it’s important to see a doctor for a proper diagnosis and treatment plan, including the right medication and dosage.

⚠️ Important Triggers and Causes

🤧 Common Cold

Caused by a virus that infects the respiratory system.
Spread through coughing, sneezing, or speaking.
Cold weather and crowded places can increase the risk, especially in rainy seasons.

🌼 Allergic Rhinitis (Hay Fever)

Caused by the immune system's reaction to harmless substances like pollen, dust mites, pet dander, or mold.
Not contagious.
Can occur year-round or seasonally, depending on the trigger.

When the immune system mistakes a harmless substance as dangerous, it releases histamine, which causes typical symptoms such as a runny nose and itchy eyes.