Normal pressure hydrocephalus Guide for patients and families
NPH or Parkinson’s disease? How to tell them apart
The short answer
Both conditions cause slow, short, shuffling steps. In normal pressure hydrocephalus (NPH) the feet are set wide apart, both sides of the body are affected alike, tremor is uncommon, and a brain scan shows enlarged fluid spaces. In Parkinson’s disease the feet stay close together, the arms swing less, symptoms usually start on one side, a tremor at rest is common, and medication helps. The difference matters because NPH is treated with an operation, not with pills.
Written and medically reviewed by Carlos Esmond Sanchez, MD, neurosurgeon in Washington, DC. Last updated November 2026.
Why the two are confused
They share the most visible sign: the walk.
Parkinson’s disease is the diagnosis most people have heard of. More than 1.1 million Americans live with it, and nearly 90,000 are diagnosed each year.1 NPH is less familiar, but it is not rare: in a Swedish population study, about 6 of every 100 people aged 80 or older met the criteria for it.2
NPH also produces some of the findings a doctor looks for in Parkinson’s. In hospital studies, slowness, stiffness and other parkinsonian features have been recorded in up to 71% of people with NPH,3 so it is understandable that Parkinson’s is often the first name given to the problem.
Two details help separate them. In a Swedish study of 168 people over 65, tremor at rest and symptoms limited to one side of the body were uncommon in those with NPH, even though other parkinsonian signs were frequent.3
The walk, side by side
NPHshort steps, feet wide apart and turned out
Parkinson’s diseaseshort steps, feet close together
Typical for agelonger, even strides
| Feature | NPH | Parkinson’s disease |
|---|---|---|
| What changes first | Walking and balance | Tremor, stiffness or slowness, often in one hand or on one side |
| Stance and steps | Feet wide apart and turned outward; short, low steps that seem stuck to the floor | Feet close together; short, shuffling steps; stooped posture |
| Arm swing | Usually kept | Reduced, often more on one side |
| Tremor at rest | Uncommon | Common |
| One side or both | Both sides alike | Usually begins on one side |
| Lines on the floor or a steady beat | Help only a little | Often help a great deal |
| Thinking | Slowed early, with poor attention | Usually affected later |
| Bladder | Urgency early, accidents later | Can occur, usually later |
| Levodopa | Little or no benefit | Usually a clear benefit |
| Brain scan | Ventricles enlarged out of proportion to the rest of the brain | Usually unremarkable |
| Main treatment | Shunt surgery | Medication |
These are typical patterns, not rules. The two conditions overlap, and the examination and the brain scan together are what separate them.
Each responds to its own treatment
The same gait-laboratory study tested treatment. The people with NPH walked again a day after 30 milliliters of spinal fluid had been removed; those with Parkinson’s walked again an hour after a dose of levodopa. In both groups, speed rose because strides grew longer. Stripes on the floor and the beat of a metronome helped the Parkinson’s group considerably and the NPH group only slightly.4
That is the logic behind the two tests used in practice: a trial of levodopa when Parkinson’s is suspected, and a spinal tap test when NPH is suspected. In a pooled analysis of 54 studies, about three of every four people with NPH improved after a shunt.5
Can a person have both?
Yes. Both become more common with age, and having one does not protect against the other. A shunt treats only the NPH. When both are present, the drainage trial shows how much of the walking problem is likely to improve with surgery, and a neurologist manages the rest.
I work one-to-one with fellowship-trained movement disorder neurologists for exactly this reason. When an evaluation points toward Parkinson’s disease or a related disorder, you leave with that neurologist’s name and a plan. What happens if it is not NPH.
When a Parkinson’s diagnosis deserves a second look
- Walking and balance were the first problem, and they are still the worst one.
- There is little or no tremor.
- Both sides of the body are affected about equally.
- Carbidopa-levodopa has made little difference.
- Bladder urgency or slowed thinking appeared early.
- A CT or MRI report mentions enlarged ventricles, ventriculomegaly or hydrocephalus.
None of these proves NPH. Together they are a reason to have the brain scan reviewed by someone who treats hydrocephalus regularly.
Do not stop a medication on your own
A change to any Parkinson’s medication belongs with the doctor who prescribed it. Stopping suddenly can cause harm.
Questions families ask
Can NPH be mistaken for Parkinson’s disease?
Yes. Both cause slow, short, shuffling steps, and in hospital studies up to 71% of people with NPH show parkinsonian features such as slowness and stiffness. A wide stance, little or no tremor, symptoms on both sides of the body and enlarged ventricles on a brain scan point toward NPH.
Does Parkinson’s medication help NPH?
Usually not. Levodopa replaces a brain chemical that is low in Parkinson’s disease. NPH is caused by excess fluid in the brain’s ventricles, which medication does not drain. A poor response to levodopa is one reason to review the diagnosis, but any change in medication belongs with the doctor who prescribed it.
Can someone have both NPH and Parkinson’s disease?
Yes. Both become more common with age. A shunt treats the NPH; Parkinson’s disease still needs a neurologist and medication. A drainage trial before surgery shows how much of the walking problem is likely to improve.
What kind of doctor tells NPH and Parkinson’s apart?
A neurologist, ideally one trained in movement disorders, diagnoses Parkinson’s disease. A neurosurgeon who treats hydrocephalus evaluates NPH and performs the drainage trial and the shunt operation. I work directly with movement disorder neurologists, so you are seen by the right specialist whichever diagnosis fits.