Essential Tremor (ET) is a common neurological movement disorder characterized primarily by involuntary, rhythmic shaking of the hands. It may also affect the head, voice and, less commonly, other parts of the body. The tremor usually becomes more noticeable when a person maintains a posture or performs voluntary movements, such as writing, holding a glass, using cutlery, or carrying out fine hand movements. The severity of essential tremor varies considerably from person to person. In some individuals, it remains mild for many years, while in others it may gradually become more pronounced and interfere with daily activities and professional life.

Symptoms of Essential Tremor

The most characteristic symptom is involuntary shaking, usually affecting both upper limbs, although it may be more pronounced on one side.

Tremor may affect:

• the hands and fingers
• the head
• the voice
• less commonly, other parts of the body

In the hands, essential tremor is typically a postural or action tremor. This means that it becomes more noticeable when the patient holds the hands in a particular position or performs a movement.

It may cause difficulty with everyday activities such as:

• writing
• using a spoon or fork
• holding a glass
• shaving or applying makeup
• using a mobile phone
• handling small objects
• professional activities requiring precision

The tremor usually decreases significantly when the affected limb is completely relaxed and is absent during sleep.

Factors That May Worsen Essential Tremor

The severity of essential tremor may fluctuate throughout the day.

Certain factors can temporarily worsen the tremor, including:

• psychological stress or anxiety
• strong emotions
• physical fatigue
• lack of sleep
• hunger
• caffeine consumption
• certain medications or stimulant substances

Identifying factors that worsen the tremor can be a useful part of its overall management.

Causes of Essential Tremor

The exact cause of essential tremor is not fully understood. Genetic predisposition appears to play an important role in many patients. Essential tremor may occur in several members of the same family, which is why the terms familial tremor or hereditary tremor are sometimes used. However, the absence of a family history does not exclude the diagnosis. Essential tremor can develop at different ages, although its prevalence increases with age.

Essential Tremor vs Parkinson’s Disease: Key Differences

Essential tremor and Parkinson’s disease are different neurological disorders, although both can cause shaking. In essential tremor, shaking is usually more noticeable when the hands are held against gravity or while performing a movement. In contrast, the characteristic tremor associated with Parkinson’s disease often occurs when the affected limb is at rest.

In addition, Parkinson’s disease may be associated with other features, including:

• bradykinesia (slowness of movement)
• muscle rigidity
• changes in walking
• reduced arm swing while walking
• balance problems in more advanced stages
• other motor and non-motor symptoms

However, distinguishing between the two conditions is not always straightforward. Different types of tremor may coexist, which is why a neurological examination is important for establishing the correct diagnosis.

Other Causes of Tremor

Not every case of hand tremor is caused by essential tremor.

Tremor may also be associated with:

• Parkinson’s disease and other parkinsonian syndromes
• thyroid disorders
• certain medications
• excessive consumption of caffeine or other stimulants
• withdrawal from alcohol or certain medications
• other movement disorders
• cerebellar disorders or other neurological conditions

For this reason, appropriate neurological assessment is recommended, particularly when tremor appears for the first time or when its characteristics change.

Diagnosis of Essential Tremor

The diagnosis of essential tremor is primarily clinical and is based on the patient’s medical history, the characteristics of the tremor, and a detailed neurological examination.

The assessment may include:

• the age at which the tremor began
• its duration and progression
• the parts of the body affected
• whether it occurs at rest, while maintaining a posture, or during movement
• factors that worsen the tremor
• the presence of other neurological symptoms
• family history
• the patient’s current medications

The neurologist may also ask the patient to write, draw a spiral, hold the hands in particular positions, or perform other movements to assess the characteristics and severity of the tremor.

Tests for the Evaluation of Tremor

There is no single blood test or imaging examination that can independently confirm a diagnosis of essential tremor. In some cases, investigations may be required to exclude other possible causes.

Depending on the patient’s medical history and the findings of the neurological examination, these may include:

• blood tests
• thyroid function tests
• Brain Magnetic Resonance Imaging (MRI) when clinically indicated
• other specialized investigations when the diagnosis remains unclear

The choice of investigations is individualized, and not every patient with tremor requires extensive diagnostic testing.

Treatment of Essential Tremor

The treatment of essential tremor depends on the severity of the symptoms and the extent to which they interfere with the patient’s daily life. Mild tremor that does not cause functional difficulties may not require medication and can simply be monitored. When tremor interferes with everyday or professional activities, pharmacological treatment may be considered. Among the medications most commonly used are propranolol and primidone, while other therapeutic options may be considered in selected cases. The choice of treatment depends on the patient’s age, the severity and distribution of the tremor, associated medical conditions, and other medications being taken.

Botulinum Toxin for Essential Tremor

In selected patients, Botulinum Toxin may be used, particularly when the tremor affects specific muscle groups and is not adequately controlled with other treatment options. Botulinum toxin may be considered in certain cases of tremor affecting the upper limbs, head, or voice. Treatment requires careful selection of the muscles involved and individualized dosing to reduce the tremor while minimizing unwanted muscle weakness.

Interventional Treatment of Essential Tremor

In patients with severe and functionally disabling essential tremor that does not respond adequately to medication, specialized interventional treatments may be considered. One established treatment option is Deep Brain Stimulation (DBS), in which electrodes are implanted in specific areas of the brain involved in the neural circuits responsible for tremor. In appropriately selected patients, MR-guided Focused Ultrasound (MRgFUS) may also be considered. The decision to proceed with an interventional treatment requires specialist assessment and careful evaluation of the potential benefits and risks.

The Impact of Essential Tremor on Daily Life

Although essential tremor is not usually life-threatening, more severe cases can significantly affect independence and quality of life. Some patients may find it difficult to write, eat, drink from a glass, or perform tasks requiring fine hand movements. Visible tremor can also cause embarrassment or anxiety in social and professional situations, leading some people to avoid activities they previously enjoyed. Assessment should therefore consider not only the severity of the tremor itself but also its actual impact on the patient’s daily life.

Neurological Follow-Up of Essential Tremor

Regular neurological follow-up helps assess the progression of the tremor, its impact on daily functioning, and the patient’s response to treatment. The development of new symptoms such as bradykinesia, muscle rigidity, significant changes in walking or balance, muscle weakness, or other neurological symptoms should prompt further evaluation. Accurate diagnosis and individualized treatment of essential tremor can significantly reduce shaking, facilitate everyday activities, and help patients maintain their independence and quality of life.