What are the other potential conditions?

Benign Tremulous Parkinsonism - This is a relatively newly described entity. It is not known with certainty if it is a distinct disease or on the spectrum of idiopathic Parkinson disease. It has been shown to have a much more benign disease course. It typically presents with a tremor that is present at rest with occasionally also being present on action. There are usually some mild subtle features of typical Parkinson disease at diagnosis. It tends not to be particularly responsive to the dopamine medications. It tends to follow a benign course and patients do not tend to develop all the other features of typical Parkinson disease. It is a diagnosis that becomes apparent over time. If tremor remains your predominant symptom over about 8 years it is considered that you have a more benign form of the disease. Autopsy studies do show a lower amount of dopamine loss in these patients than in those with typical Parkinson disease.

Essential Tremor - This is the most common neurologic cause of an “action” tremor. This simply means the tremor comes on with action. So patients will often complain that the tremor is most bothersome when they go to use the hand such as to pick up a cup of tea or write. It usually involves both arms but it can also involve the head, voice, chin, trunk and legs. In general, distinguishing between a tremor that is due to Parkinson disease and one that is due to an essential tremor is straightforward. However, there are patients who will have features of both an essential tremor and also that of a Parkinson tremor and this can make the diagnosis more challenging. Often when the underlying diagnosis is Parkinson disease there will be more subtle findings that your neurologist will pick up on the clinical examination.

Multiple System Atrophy - This is an unusual condition that sometimes presents in a similar manner to Parkinson disease. However, there are some distinctive features that will help your neurologist make this diagnosis. Most patients with multiple system atrophy will not respond to the medication that is given for Parkinson disease. People with multiple system atrophy will often have a problem with their autonomic nervous system causing dramatic drops in blood pressure on standing up (see autonomic disorders page). In general, patients with multiple system atrophy will present with symptoms in both arms or legs (as opposed to just one side of the body which is more typical for Parkinson disease). Multiple system atrophy does not frequently cause a tremor. Multiple system atrophy does not tend to cause dementia or cognitive problems.

Progressive Supranuclear Palsy - This is another unusual condition that can often be confused with Parkinson disease especially in its early stages. One of the hallmarks is early falls- as in this is what brings the patient to their GP. This is due to rigidity in the trunk muscles so the patient has a very stiff posture while they are walking and this can lead to multiple falls. Another hallmark of this condition is a failure of the eyes to be able to look downwards or upwards. The neck can become stiff and the speech can take on a raspy quality. Again, patients with this condition tend to have a poor response to the medication that is used to treat Parkinson disease.

Cortico-basal Degeneration - This is an unusual progressive neurodegenerative condition. It is caused by build-up of a protein in the brain surface (cortex) and in deeper structures of the brain (basal ganglia). It can cause a lot of different symptoms including muscle spasms, rigidity and stiffness of muscles, poor coordination, poor balance, abnormal muscle postures (often referred to as “alien limb” where the arm moves on its own). It can also affect memory and thinking as well as speech and swallow function. It progresses gradually over about 6-8 years. There are no specific treatments for it aside from symptom control.

Drug-induced Parkinsonism - This can occur from drugs that block dopamine in the brain. The most common ones are anti-psychotic medications. However, drugs for more simple conditions such as nausea and dizziness can be a culprit also as they work by blocking dopamine in the brain. Therefore, these medications such as stemetil and maxalon should only be used in the short term. When it comes to anti-psychotic medication the patient may need these in the longer term. Therefore, it is best to try and find one with the lowest risk of parkinsonism as a side-effect and your neurologist, psychiatrist and GP should be able to help in this regard. It is of utmost importance that none of these medications are stopped abruptly. If you are concerned you should contact the doctor who prescribed the medication. Once the offending drug is stopped there should be an improvement although this does not happen in 100% of patients. Also the improvement may take some time. The most common symptom of a drug induced parkinsonism is slowness of movement and rigidity and it tends to be on both sides of the body at the start. Although like anything in medicine this is not an absolute and there are some patients who will present with a tremor. The diagnosis will be made by your neurologist. If the symptoms persist despite coming off the offending drug then the medication used for treatment will be an anti-cholinergic medication (described below).