Allergies or Sinus Infection: How Do You Know?

You have a stuffy nose, a headache and keep sneezing—is it caused by allergies or a sinus infection? It can be difficult to tell, especially during allergy season or if you have year-long allergies. To add to the confusion, allergies can lead to a sinus infection (or sinusitis) too.

It’s important to get the right treatment. How do you know where to start? Here’s the difference between them:

Signs of Allergies

An allergic reaction to pollen, grass, animal dander, dust, mold or other allergens usually happens pretty quickly—from minutes to hours—after exposure. If you’re allergic to pollen and you are outside gardening or exercising, you may start sneezing or have watery, itchy eyes right away or within 20 minutes or so of being outside.

Your nasal passages and sinuses may become irritated and swell because they’re trying to flush out the pollen, dander or other allergens. The swelling can block mucus from draining properly, leaving you congested, possibly causing sinus pain and pressure. If left untreated, this can lead to a sinus infection.

Having this reaction—sneezing, congestion, sinus pain—in response to a trigger is key to determining whether it’s allergies or sinus infection. Of course, if you’re new to allergies, you might not realize the trigger right away. Itchy or red eyes are also key—sinusitis does not cause itchy, red eyes. Your eyes might water from sinus pain, but with allergies, the watery, itchy, red eyes are an immune response to the allergen.

Signs of Sinusitis

Even though allergies can lead to a sinus infection, that infection is typically caused from a bacteria or virus. Symptoms of a sinus infection can include:

  • Headache
  • Pain or tenderness around your forehead, eyes, cheeks and/or nose
  • Stuffy or runny nose
  • Post-nasal drip
  • Sore throat

The distinguishing sign of a sinus infection is the color and thickness of the liquid draining out of your nose. With allergies, nasal discharge is usually clear or mostly clear. With a sinus infection, the discharge is often a thick yellowish or greenish substance. Check your tissue after blowing your nose because the doctor will ask you what your nasal discharge looks like.

Treating Allergies and Sinusitis

If you have allergies, you will benefit from taking an antihistamine. Your doctor may recommend one you can buy off the shelf at local stores, pharmacies and supermarkets, or he or she may prescribe an antihistamine or seasonal allergy shots. Your symptoms should lessen and go away within hours to days of taking the medicine. (Allergy shots come in a series and may need longer to take effect.)

For a sinus infection, depending on the cause (virus or bacteria), you may be prescribed an antibiotic or your doctor may just tell you to rest, drink plenty of fluids, and use an over-the-counter sinus medicine like BC® Sinus Pain & Congestion to help relieve the pain and congestion.

Our quick-acting powder sinus medicine contains a pain reliever, decongestant and antihistamine, which is helpful if your allergies contributed to your sinus pain and congestion.