Several conditions look a lot like Parkinson’s from the outside. In fact, more than half of people with atypical parkinsonism are initially diagnosed with Parkinson’s, with the correct diagnosis reported to arrive about three years later on average. Symptoms alone often can’t tell them apart perfectly, so if your diagnosis is unclear or things progress differently than expected, asking for a re-evaluation is an option.
Essential tremor — the tremor most often confused with Parkinson’s
Essential tremorThe tremor condition most often confused with Parkinson's. It gets worse during movement rather than at rest, and usually appears on both sides of the body at once.Learn more is a more common tremor condition than Parkinson’s. Parkinson’s tremor appears when you are still (rest tremor) and shows up first on one side of the body, whereas essential tremor gets worse during movement — reaching out a hand, gripping an object — and often appears on both sides of the body. Another important difference is that it doesn’t come with other motor symptoms such as bradykinesia or rigidity.
MSA, PSP and CBD — atypical parkinsonism
Conditions that don’t respond to levodopa the way Parkinson’s does are grouped together as atypical parkinsonismAn umbrella term for conditions that look like Parkinson's but progress differently and respond differently to medication. More than half are diagnosed as Parkinson's at first, with the diagnosis corrected about three years later on average.Learn more. There are three main ones.
- Multiple System Atrophy (MSA): comes with autonomic problems — severe dizziness on standing, large swings in blood pressure — and difficulty controlling urination.
- Progressive Supranuclear Palsy (PSP): characterized by difficulty moving the eyes up and down. Balance problems and falls are severe from early on, and changes in thinking and behavior appear relatively early too.
- Corticobasal Degeneration (CBD): one side of the body stiffens and jerks involuntarily, with dystonia locking the hands and feet into abnormal postures.
Dementia with Lewy bodies
Dementia with Lewy bodies (DLB)A dementia caused by Lewy bodies (clumped alpha-synuclein) accumulating widely across the brain. Memory problems, visual hallucinations and motor symptoms similar to Parkinson's appear together.Learn more is a condition in which memory problems and confusion, difficulty sustaining attention, visual hallucinations of things that aren’t there, and motor symptoms similar to Parkinson’s all appear together. Parkinson’s can also lead to dementia after many years (Parkinson’s disease dementia), and the two are usually told apart by timing: if motor symptoms come first and dementia follows more than a year later it is generally called Parkinson’s disease dementia, while if cognitive symptoms arrive at about the same time as the motor symptoms or before them, it is generally called dementia with Lewy bodies.
Sometimes medication is the cause
Some antipsychotics and drugs that stimulate gut motility block dopamine receptors in the brain, and can bring on drug-induced parkinsonismWhen certain medications block dopamine receptors in the brain and cause symptoms similar to Parkinson's. It usually appears symmetrically on both sides of the body, and in many cases improves gradually once the drug is stopped.Learn more. Unlike Parkinson’s it usually appears symmetrically on both sides of the body, and only about one in three people have tremor. Stopping the responsible drug often leads to gradual improvement over 4–18 months, though for some the symptoms remain.
When blood vessels or cerebrospinal fluid are behind it
Normal pressure hydrocephalus (NPH)A condition caused by an excessive build-up of cerebrospinal fluid in the brain, with difficulty walking, cognitive decline and loss of bladder control as its classic symptoms. Telling it apart matters especially, because a procedure can improve the symptoms.Learn more is a condition in which cerebrospinal fluid builds up excessively, bringing difficulty walking, decline in cognitive function and loss of bladder control together. Unlike other parkinsonian conditions, symptoms can improve after a procedure to drain the fluid, which makes distinguishing it accurately especially important. Meanwhile vascular parkinsonismParkinsonism caused by repeated damage to small blood vessels in the brain. Symptoms stand out in the legs, rest tremor is rare, and the response to levodopa is weaker than in Parkinson's.Learn more, which comes from repeated damage to small blood vessels in the brain, shows a “lower-body parkinsonism” pattern in which symptoms stand out in the legs more than the arms; rest tremor is rare, and the response to levodopa is known to be markedly weaker than in Parkinson’s.
What you can do now
If your symptoms progress differently from what you first expected, or the medication doesn’t work as well as you hoped, it’s important to tell your care team exactly that. A diagnosis isn’t settled perfectly in one sitting — more often it is refined over time, by watching how the symptoms change.
This article is not a substitute for medical diagnosis or treatment. If your diagnosis is unclear or it’s worrying you, please talk with your care team.
