Do You Lose Your Sense of Smell with PSP?

Yes. If you have movement symptoms that look like Parkinson’s disease but your sense of smell is still relatively preserved, doctors consider this a major clinical clue—often called a “red flag”—that points away from typical Parkinson’s. Instead, it suggests an atypical parkinsonian syndrome like Progressive Supranuclear Palsy (PSP) or Multiple System Atrophy (MSA) ^[1][2].

Why Your Sense of Smell Matters

When diagnosing movement disorders, neurologists look closely for hyposmia, which is a medically reduced ability to smell and detect odors ^[2].

In idiopathic (typical) Parkinson’s disease, a significant loss of smell is one of the most common and earliest signs, often occurring years before any movement problems appear ^[1][2]. However, in people with PSP, olfactory function (the sense of smell) is typically preserved or remains normal for your age ^[1].

This striking difference makes checking your sense of smell a valuable, non-invasive way for doctors to help tell the two diseases apart ^[1][2].

How Doctors Use This Information

Distinguishing between Parkinson’s and PSP can be challenging, especially in the early stages when the physical symptoms look very similar ^[3]. Doctors use several tools to get a clearer picture, and your preserved sense of smell is a helpful piece of the puzzle alongside other diagnostic tests:

• Clinical Smell Tests: Your doctor might use formal tests (like the UPSIT or Sniffin’ Sticks) to objectively measure your sense of smell, rather than relying on self-reporting alone. This helps accurately distinguish Parkinson’s from atypical syndromes like PSP ^[2].
• Brain Imaging: MRI scans can look for specific patterns of brain shrinkage. For instance, changes in the midbrain (sometimes called the “hummingbird sign”) strongly suggest PSP rather than Parkinson’s ^[4][5].
• Specialized Scans: While a DaTSCAN can confirm you have a parkinsonian condition, it cannot easily tell PSP and Parkinson’s apart. Instead, specialized imaging like an FDG-PET or tau PET scan may be used to look for specific patterns in the brain that improve the accuracy of differentiating PSP from other neurodegenerative disorders ^[3][6].

What This Means For You

Having a normal sense of smell for your age doesn’t definitively confirm you have PSP, as other conditions can also preserve your sense of smell ^[2]. However, it is an important piece of information that you should clearly communicate to your medical team. It tells your neurologist that they need to look closely for other signs of PSP. For example, they might check for specific changes in your eye movements (such as difficulty looking up or down) or early problems with balance and backwards falls ^[7][4].

Knowing exactly which condition you have is crucial. It helps you and your doctor build the most effective care team, anticipate future symptoms, and understand your treatment options. For example, typical Parkinson’s medications often provide limited relief for people with PSP, so getting the correct diagnosis ensures your care plan is tailored specifically to your condition rather than a misdiagnosis ^[3].