Both sinus headaches and migraines can cause intense head pain, sinus pressure, and a runny or stuffy nose. This is mainly because all the nerves that gives your head and face feeling are packed closely together.

Your trigeminal nerve is a pain pathway that provides sensation to the head and face and is thought to highly involved in migraines, Jessica Ailani, M.D., associate professor of neurology at MedStar's Georgetown University Hospital and director of MedStar Georgetown Headache Center, tells SELF. It happens to be connected to a bundle of nerves called the sphenopalatine ganglion. Also known as the SPG, these nerves help control autonomic (i.e., involuntary) functions like breathing. The connection between the trigeminal nerve and the SPG is why people with either migraines or sinus headaches can have head pain and pressure that come along with issues like a runny or stuffy nose. (Here are 11 interesting facts about migraine)

To make things even trippier, sinus headaches and migraines can share triggers like weather and seasonal changes. “It can get very confusing when patients decide what kind of specialist to see,” Dr. Weber says.

It's important to know the differences between migraine, headache and sinus

Here are some clear signs you may indeed have a sinus headache:

  • You have other signs of infection, like a fever or a cough:These aren’t likely to come along with a migraine, Dr. Ailani says. If you’re experiencing them along with congestion and head pain, a sinus headache could be to blame.
  • When you blow your nose, you see green or yellow mucus:Changes in mucus color can signal that you have a bacterial sinus infection instead of a migraine. And these often can lead to sinus headaches.

Here are a few hints that migraines and not sinus headaches are your issue:

  • You’re experiencing aura:Having pain that comes along with aura—sensory changes like seeing weird shapes or flashes of light, vision loss, hearing random noises, physical numbness or weakness, smelling or tasting strange things, and more—is one pretty clear sign you’re dealing with migraines instead of sinus headaches, Dr. Weber says. But not everyone with migraines experiences aura; only around 15 to 20 percent of people with migraines do, according to the Cleveland Clinic. And it’s true that sinus headaches can cause sensory issues like a decrease in smell and taste, too. Still, these types of sensory changes are much more likely to accompany migraines than sinus headaches, Dr. Weber says.
  • You’re nauseous, vomiting, or experiencing sensitivity to noise or bright light:These are classic migraine symptoms that don’t typically occur with sinusitis, according to the Mayo Clinic.
  • Sinus infection treatments don’t help your symptoms as much as you’d expect:Sinus infections are typically treated with things like nasal sprays and decongestants, allergy shots, or potentially antibiotics if you have a severe bacterial sinus infection, according to the Mayo Clinic.

Since migraines and sinus infections have similar symptoms, some of these treatments may help relieve things like a runny or stuffy nose that accompanies a migraine, Dr. Ailani says. But while they can completely eradicate a sinus infection, they won’t do the same thing for a migraine. Figuring out a migraine treatment plan is typically more involved and can vary from taking a range of pain relievers to using triptans, which block pain pathways, to trying preventive medications that attempt to stop the pain from starting in the first place. (Learn more about what happen to your body when you have a migraine)

“If you actually have a sinus headache, the pain should recede as soon as the congestion does,” Dr. Weber says. “If [sinus infection medications] aren’t working, you may have the wrong diagnosis,” Dr. Weber says.

The nasal symptoms of migraine and the symptoms of a sinus problem are similar that it´s sometimes hard for doctors to tell the difference.  If you have symptoms regularly around your migraines, the two may be related.

Migraine attacks often occur together with nasal symptoms. Whether the symptoms occur due to migraine or them because migraine is controversial. If mucosal congestion or contact of the nasal mucosa is considered to trigger a migraine or to exacerbate pain, the reduction in frequency and intensity of migraine pain will be possible by the treatment of pathologies of the nose.

If the way things smell to you seems a bit different just before a migraine comes, it may be from the nerves in your brainstem firing.  Some scents may seem too strong, or you may smell things that aren´t there.

Nasal symptoms: 

  • Sinus pressure and pain
  • Stuffy nose
  • Smell sensitivity
  • Sense of smell hallucinations (you may smell things that are not there)

About 45% of people with migraines say they have sinus symptoms like tearing, runny nose and nasal congestion during their attacks.

Find out more about migraines, their causes, symptoms and treatments here.