Diseases and Conditions

Parkinson's disease

Diagnosis

No specific test exists to diagnose Parkinson's disease. Your doctor trained in nervous system conditions (neurologist) will diagnose Parkinson's disease based on your medical history, a review of your signs and symptoms, and a neurological and physical examination.

Your doctor may suggest a specific single-photon emission computerized tomography (SPECT) scan called a dopamine transporter scan (DaTscan). Although this can help support the suspicion that you have Parkinson's disease, it is your symptoms and neurologic examination that ultimately determine the correct diagnosis. Most people do not require a DaTscan .

Your doctor may order lab tests, such as blood tests, to rule out other conditions that may be causing your symptoms.

Imaging tests — such as an MRI, ultrasound of the brain, and PET scans — also may be used to help rule out other disorders. Imaging tests aren't particularly helpful for diagnosing Parkinson's disease.

In addition to your examination, your doctor may give you carbidopa-levodopa (Rytary, Sinemet, others), a Parkinson's disease medication. You must be given a sufficient dose to show the benefit, as low doses for a day or two aren't reliable. Significant improvement with this medication will often confirm your diagnosis of Parkinson's disease.

Sometimes it takes time to diagnose Parkinson's disease. Doctors may recommend regular follow-up appointments with neurologists trained in movement disorders to evaluate your condition and symptoms over time and diagnose Parkinson's disease.