Types of tremor
There are two main types of tremor:
- Physiological tremor (normal tremor) - this occurs in all of us and is quite normal, for example when an outstretched limb is held against gravity. It is exacerbated at times of stress, anxiety or fear when it is called “enhanced physiological tremor”.
- Pathological tremor (abnormal tremor) – this occurs as a result of conditions such as Parkinson’s and Essential Tremor (ET) which affect the nervous system. These tremors are usually classified, or described, according to the circumstances in which they arise, for example:
- rest tremor which occurs when a body part is completely at rest and supported (such as a hand supported by an armchair). This usually, but not always, stops when an intended action is carried out
- action tremor which occurs when an intended movement is made, such as moving a limb from one point to another or when a particular posture is maintained. Action tremor seen when the limb is held in posture is called postural tremor.
Essential Tremor (ET) is a relatively common condition that results in trembling in the hands or arms, which in some cases can subsequently spread the head, legs, trunk or voice. ET is quite often confused with Parkinson’s but in Parkinson’s the trembling is usually more apparent when the hands are resting on the affected person’s lap or when walking. ET is a form of ‘action tremor’ - it is more pronounced when the hands are performing an action, for example holding a cup or using cutlery.
For more detailed information see Essential tremor.
Also see, National Tremor Foundation website.
Tremor in Parkinson’s is caused by reduced levels of dopamine as a result of the loss of dopamine-producing cells in the brain. This is often one of the first signs of Parkinson’s and it is thought that approximately 70% of people with the condition have a tremor at the time of diagnosis.
Rest tremor is common in Parkinson’s and occurs when your body is relaxed, for example when on a sofa or lying in bed. ‘Pill rolling’ rest tremor is typical, so called because it looks like you are trying to roll a pill between your thumb and forefinger. Rest tremor can also affect your legs, lips and tongue. Head tremor, which is relatively common in Essential Tremor is extremely rare in Parkinson’s.
Action tremor is also common in Parkinson’s, particularly in the hands. As it occurs when you are trying to do a specific activity, for example holding a cup or writing, it is usually more disruptive.
Tremor generally worsens over time but this tends to be a slow process, although the rate of progress varies from person to person. How it affects you can change from day to day too. It typically begins in the fingers of one hand and then spreads to the arm. It can affect the foot on the same side of the body and in some cases may begin in a foot and spread upwards. Eventually it may affect the other side of the body too.
Speak with your doctor if you are worried about a tremor. A movement disorder specialist will usually be able to distinguish between Parkinson’s tremor and Essential tremor by carrying out a clinical assessment.
There is no cure for tremor, but there are many ways to manage it.
Management of tremor
There is no cure for tremor, but there are many ways to manage it. Good control of tremor requires optimal control of Parkinson's with medications.
All involuntary movements, including tremor, are worsened by emotional or physical stress, anxiety, fatigue and illness. Many people find that complementary therapies which promote relaxation and reduce stress help them. Exercise may also help to boost energy levels, reduce fatigue and improve wellbeing. Changes to your diet may also be beneficial.
Stimulants such as caffeine, coffee, chocolates and recreational drugs also worsen tremor so it is a good idea to watch how much of these you consume. Alcohol withdrawal can also cause tremor.
Psychological approaches, including cognitive behavioural therapy, relaxation therapies and medication can also be helpful. Talk with your healthcare team so that they can put you in contact with professionals who can help.
Many people have discovered and developed strategies that help them to reduce or overcome tremor – their own personal coping strategies. Although these won’t work for everyone, watching some of these video clips in 'Coping Strategies - Tips & Tricks' may help you discover and develop strategies of your own.
For some people dopaminergic medications and the various forms of levodopa will relieve tremor but in others they may not be effective. These differences in responsiveness have yet to be satisfactorily explained. You will need to work with your doctor to establish a medication regime that works best for you.
Some medications can cause or worsen tremor, for example tranquillisers and anti-sickness drugs. Some antidepressants, asthma and epilepsy medications can also make your tremor worse. Always check the patient information leaflet that comes with medications to see if they are thought to cause or worsen tremor.
Deep brain stimulation
Deep brain stimulation (DBS) is used in some people with Parkinson’s to help control their movement (motor) symptoms, including tremor. DBS passes a small current through precisely targeted areas of the brain which appears to block motor symptoms.
DBS is not suitable for everyone. This surgery and its potential risks and benefits should always be discussed with an experienced doctor.
See also, Deep brain stimulation.
Our thanks to Parkinson's UK for permission to use the following source(s) in compiling this information:
Tremor and Parkinson’s.