I Am Not Sure If I have a Sinus Infection or Allergies. How Do I Tell?

If you are feeling miserable with a runny nose, constant sneezing, and nasal congestion, you want to know how you can get back to normal. You know these symptoms can be signs of an allergy or a sinus infection, but it is hard to tell for sure which one you have. How can you differentiate between a sinus infection and an allergy to obtain the proper treatment?

What Are the Signs of a Sinus Infection?

A virus or bacteria causes a sinus infection. You are at risk for a sinus infection, also called sinusitis, if you have had a previous cold or exposure to any form of smoking.   

Infected fluid collects in the sinuses, which are air-filled pockets around your nasal cavity. The sinuses then become inflamed, and mucus builds up in the nose.

Other signs of a sinus infection include the following: 

  • Bad Breath
  • Cough
  • Facial pain or pressure
  • Fever
  • Fatigue
  • Headache
  • Mucous from the nose that is yellow or green
  • Sore throat
  • Stuffy nose

Sinusitis can be confused with rhinitis, which only occurs in the nasal passages. Rhinitis is nasal inflammation and irritation and occurs with colds and allergies. A sinus infection can also occur during or after seasonal allergies, making diagnosing it especially difficult. 

What Are the Signs of Allergies?

An allergy occurs when your immune system sees a substance as harmful and overreacts. Histamines are released in your bloodstream during the reaction to combat the allergen. This immune response causes the following allergy symptoms:

  • Headache
  • Itchy, watery eyes
  • Nasal congestion
  • Running nose
  • Sneezing

If you experience seasonal environmental allergies, you may notice the symptoms are more apparent at different times of the year. Certain plants or trees may bloom, releasing allergens in the air to cause allergic rhinitis. Other causes of allergies include dust mites and pet dander. 

Can Any Tests Tell the Difference Between Sinus Infections and Allergies?

When your symptoms become bothersome, you may need to make an appointment with your doctor to pinpoint the reason for your ailments. The provider will ask detailed questions regarding your symptoms and how long you have suffered. Then, the provider will perform a physical exam by assessing facial tenderness and examining your nose and nasal congestion. Finally, they may need to do further testing, which may include the following:


  • Nasal endoscopy: The healthcare provider inserts a small lighted tube through your nose to inspect your sinuses visually
  • CT scan: A detailed picture of the sinuses
  • Nasal and sinus samples: A culture may be indicated if sinusitis persists 
  • Allergy test: A skin test that will identify if an allergen is causing your symptoms

After the appointment, the doctor can determine if you have allergies or a sinus infection and prescribe the appropriate treatment.

What Are the Treatments for Sinus Infections?

If your doctor determines you have a sinus infection, they will prescribe medications and treatments to help you feel better.  

Antibiotics are the standard treatment for a bacterial sinus infection. Antibiotics require a prescription, and you must complete the entire course of the medication, even if your condition improves. However, a virus generally causes acute sinusitis, and antibiotics are not an indicated treatment.

For both bacterial and viral sinus infections, your provider may suggest prescription and over-the-counter medication to help relieve the symptoms. 

  • Nasal decongestant sprays and medications help shrink the swollen nasal passages that come with a sinus infection, easing the fluid out of the inflamed nasal passages.
  • Oral decongestants, in the form of a pill or liquid, will relieve your stuffy nose.
  • Nasal saline washes will clear the thicker mucous from the nasal passages.
  • Over-the-counter pain relievers like acetaminophen and ibuprofen will help with headaches and facial pain. 

What Are the Treatments for Allergies?

Although you can not fully prevent an allergy, you can avoid the substance you are allergic to. For example, if you experience seasonal allergies, staying indoors during the time of the year you suffer from the conditions may be helpful. If you are allergic to dust mites, make sure to wash your bedding at regular intervals. If pet dander is the allergen culprit, wash your hands after petting your furry friend.

Allergy treatment also includes taking certain medications:

  • Antihistamines will block the trouble-producing histamines from causing itchy eyes and a runny nose. This medication can be short-acting, such as diphenhydramine, or longer-acting pills that you take daily.
  • Nasal corticosteroids are a sinus allergy treatment that decreases nasal inflammation and allergy congestion.
  • Immunotherapy, or allergy shots, taken consistently over several years will desensitize you to the allergic reaction. 

Paying close attention to symptoms can help your provider determine if you have a sinus infection or allergy. With the proper diagnosis, you can start the best course of medically reviewed treatment to relieve your symptoms. You will be feeling back to normal again.


Bishop, S. (2013, April 12). Pay Close Attention to Symptoms to Determine if Cause is Sinus Infection or Allergies. Mayo Clinic. 

Cherney, K. (2018, November 21). Do You Have Allergies or a Sinus Infection?. Healthline. 

WebMD. (2023, November 15). Is It Sinusitis or Allergies?. 


Sara Egnatz

Sara Egnatz BSN, RN-BC is a registered nurse and a freelance writer. She and her husband are “free-birds” after launching their three adult children from the nest. In her spare time, she loves to read historical fiction and hike the beautiful North Carolina State Parks.