US Pharm. 2015;40(1):12-15.

There are several occasions in the typical workweek when pharmacists field questions about medical conditions that cannot be treated with nonprescription products. One such condition is tremor. Perhaps a patient has noticed a tremor for the first time. It may also be that the person has lived with a tremor, but it has worsened to the point where the patient asks the pharmacist whether a physician appointment is necessary.

Definition of Tremor

Involuntary movements are a group of disorders in which the body undergoes motions that are not under the person’s control. The most common of these is tremor.1-3 Tremor is a rhythmic set of motions described as trembling, shaking, or oscillatory (i.e., back and forth). The primary site of tremor is the hands and arms. However, tremor can occur in other body sites, such as the head, face, voice, trunk, and legs.

Epidemiology of Tremor

Tremor can affect any age group, but the primary sufferers are those who are middle-aged or older.1 There is no gender difference, although some types of tremor appear to be genetically inherited.2

Manifestations of Tremor

Tremor can be constant or intermittent, and temporary or permanent. Tremor of the hands can be so severe that the patient has difficulty writing or drawing. If the patient’s vocation requires these activities, tremor forces early retirement. Even after the patient has retired, tremor can become so obtrusive that it is no longer possible to carry out normal activities such as bringing food or drink to the mouth without spilling. If the voice is affected, others notice a shaking quality to the speech. Other manifestations are described more fully below, under the different categories of tremor.

Triggers of Tremor

Tremors can be initiated or worsened by such factors as life stressors, anxiety, strong emotions, and physical exhaustion.1-3 Some patients notice that coffee or other caffeinated drinks can cause tremor or worsen existing tremor. Drinking alcohol to excess or withdrawing from alcohol addiction can also cause tremor.

Types of Tremor Related to Movement

A common method of classifying tremor is how it relates to the patient’s movement or lack of movement.1 The first type of tremor is known as resting tremor, common with Parkinson’s disease. Patients with resting tremor experience shaking of the limbs (especially the hands and fingers) when those body parts are fully relaxed and in repose. Tremors can be seen when the hands are lying in the lap while sitting or hanging at the sides while standing or during ambulation.

The second type of tremor is known as action tremor, because it occurs when the patient moves a body part. Action tremors are referred to as postural if they occur when a body part is being held against gravity, such as by extending the arms out or away from the body. They are classified as kinetic
if manifested during movement of the body part. Action tremors are known as intention tremor if they occur during a directed movement toward a target, as when a patient is asked to touch a finger to his or her nose during a medical examination. If the patient’s tremor begins during goal-oriented tasks requiring a high skill level (e.g., speaking or writing), the patient is said to have task-specific tremor. The final type of action tremor is isometric tremor, occurring when the patient experiences a voluntary muscle contraction against a stationary object.

Measurement of Tremor

Specialists assert that there is no method for measuring tremor or rating its severity that has been universally accepted.4 Researchers have developed numerous scales that rate the patient on such factors as degree of disability and abilities that the patient retains. Most scales also measure tremor frequency and amplitude.4 Frequency is measured as the number of oscillations per second, and amplitude is measured by the distance over which the limb oscillations occur (e.g., 10 mm) and/or the angular degree of displacement of the limb (e.g., 35 degrees). Amplitude is the more troublesome of the two for patients.4

Major Categories of Tremor

While there are many causes of tremor, clues such as the relationship to movement can point to the cause. The National Institutes of Health has explained several categories of tremor.1 

Essential Tremor: Formerly referred to as benign essential tremor, this is the leading form of tremor, affecting as many as 10 million U.S. residents.1,5 Most patients with essential tremor are aged ³65 years.6,7 The frequency of essential tremor is six or more per second. The most common presentation is an action tremor of the hands, but the patient may notice tremor in the head, voice, eyelids, tongue, trunk, and (in rare cases) the legs and feet.1,6 When the head is involved, it undergoes a back-and-forth or up-and-down (nodding) motion. When the legs are affected, the patient does not walk as he or she normally did prior to the onset of tremor.

Essential tremor causes problems when the patient attempts to carry out normal daily activities requiring mastery of fine motor skills, such as eating, shaving, writing, and applying makeup. The ability to accomplish these tasks can be severely impaired.5 Some patients have only a mild tremor that does not worsen, but other patients experience a progressive form that begins unilaterally and spreads bilaterally within a few years of onset.

Essential tremor can be triggered by such factors as stress, physical exhaustion, hypoglycemia, fever, or strong emotions. Children of those affected with essential tremor have a 50% risk of inheriting it.6 Research into possible causes of essential tremor implicates mild cerebellar degeneration as causal. Patients with essential tremor can be reassured that it does not have any effect on their life span.5

Parkinsonian Tremor: When patients notice this tremor, it is often the first signal that Parkinson’s disease is present.1 Parkinsonian tremor is a resting tremor, in which the hands exhibit a repetitive motion of the fingers and thumbs that is described as “pill rolling,” in recognition of the method by which pharmacists made pills in the era before mass-produced tablets became widely available. At least one-fourth of Parkinson’s patients also have an action tremor.1 Other areas affected are the chin, lips, legs, and trunk. The onset is usually after age 60 years, and the tremor is worsened by emotions and stress.

Dystonic Tremor: This type of tremor is most common in patients with a preexisting condition known as dystonia. In this condition, sustained involuntary muscular contractions induce abnormal reactions in the dystonic body part. The reactions include twisting, repetitive motions, and an abnormality of position or posture, such as writer’s cramp or twisting of the neck (torticollis). These patients may experience dystonic tremor in the dystonic body part or in any other body part.5 Dystonic tremors occur intermittently. The quality of dystonic tremor resembles essential tremor, but touching the areas affected by the tremors can help reduce their severity, and complete rest can reduce their occurrence.

Cerebellar Tremor: This type of tremor may arise from cerebellar lesions or damage resulting from such circumstances as stroke, tumor, multiple sclerosis, alcohol use, or degenerative disorders that are genetically transmitted.1 It manifests when patients are asked to perform an intentional movement, such as pressing a test button or touching the tip of the nose. Cerebellar tremor may be accompanied by nystagmus, gait irregularities, and/or speech abnormalities.

Psychogenic (Functional) Tremor: Psychogenic tremor often coexists with psychiatric conditions such as conversion disorder.1,8 Psychogenic tremor can manifest as any or all of the possible types of tremors. The onset and end of the tremor is usually sudden; it is exacerbated by stress, and its intensity drops or disappears when the patient becomes distracted. It can also be part of such conditions as malingering or factitious disorder, when the patient feigns illness.8

Orthostatic Tremor: With this type of tremor, patients stand suddenly and become unsteady, also experiencing high-frequency, almost imperceptible, rhythmic contractions of the legs and trunk. Placing a stethoscope to the thigh muscles can allow the physician to detect the tremor. Furthermore, symptoms cease if the patient sits, begins to walk, or is lifted from the ground.1

Physiologic Tremor: All healthy people invariably have physiologic tremor to some degree. The voluntary muscle groups manifest this tremor, and potential causes are strong emotions, heavy metal toxicity, hyperthyroidism, fever, hypoglycemia, exhaustion, caffeine or other stimulants, or withdrawal from alcohol addiction.1 Since this tremor is usually imperceptible, the physician may place a piece of paper on the patient’s hands when the arms are extended. Physiologic tremor can be seen as the paper flutters.

What to Tell Patients With Tremor

Most tremors have no cure (e.g., cerebellar tremor). However, the potential for ameliorating the condition depends on the cause of the tremor. Therefore, the obvious first step for patients asking about tremor is referral to a physician. Referral is especially important in the following situations: 1) The tremor is worse when the patient is resting but improves with purposeful movement, such as reaching for an object; 2) the tremor is prolonged, unusually severe, and/or causes problems with the patient’s normal daily activity; and 3) the patient has symptoms accompanying the tremor, such as headache, weakness, abnormal movements of the tongue, tightening of the muscles, or other body movements that cannot be controlled.3

Following diagnosis of the specific type of tremor, the patient’s physician may attempt treatment in some cases. Essential tremor may be minimized with beta-blockers, and clonazepam helps treat dystonic tremor and primary orthostatic tremor.1,9 Primidone may be useful in essential tremor and primary orthostatic tremor. Botulinum toxin injections can improve dystonic tremor, as well as voice and head tremors.

Physical therapy and surgery may provide relief from tremor. Psychogenic tremor should be approached by first addressing the underlying psychological issue. No nonprescription product or device is proven safe or effective for tremor, although some of the self-help steps on this month’s Patient Information page may provide some relief.

PATIENT INFORMATION

Causes of Tremor

In most people, tremor is not caused by any serious underlying disease. In fact, many people do not need treatment because the tremor does not cause any major problems in their life. However, tremor can be caused by such conditions as Parkinson’s disease. Furthermore, in more serious cases, it can disrupt your life, making it almost impossible to eat or drink.

In order to rule out serious underlying causes of tremor, it is advisable to seek a physician for a diagnosis. Your doctor can also help you locate sources that can assist in coping with daily activities if tremor is disabling. 

Self-Help Steps to Minimize Tremor

There are no nonprescription products or devices that can stop tremor. However, there are some useful self-help steps that may minimize its effect on your life. 

Get Enough Sleep: Many tremors worsen when you are tired or sleepy. It may be helpful to modify your work schedule so that no single day has too much physical activity. Try to engage in light activity each day to help ensure that you have fewer days with excessive fatigue.

It is also important to sleep enough hours to prevent fatigue. While everyone differs in their sleep requirements, most people are aware of the number of hours they need to feel fully rested. Try to get those hours of sleep each night. Choose a specific time to go to sleep and awaken and try to stick to that. Don’t stay up late playing video games or watching movies. 

Reduce Stress: Stress and anxiety can also worsen tremor. It is often extremely difficult or even impossible to alter your life circumstances to eliminate stress and anxiety, especially when they are caused by your job and/or family. However, you may find counseling helpful, and you may also learn interventions such as meditation, deep breathing, and deep relaxation. 

Avoid Caffeine and Alcohol: Caffeine is a common cause of tremor, and the more you drink, the worse your tremor will be. The only medically justified use for coffee, tea, colas, energy drinks, and other caffeinated products is to get an energy boost when performing boring, routine work. Most people are recreational users, and many are addicted to caffeine. If you wish to minimize tremor, it is recommended to stop all caffeine intake. The withdrawal symptoms are very unpleasant, but once you are free of the addiction, you may find that your tremor is greatly reduced or has disappeared altogether.

Alcohol abuse is also a source of tremor. If tremor is causing severe life problems, abstaining from alcohol may improve or eliminate the tremor. Not drinking alcohol will contribute to your overall health as well.

Remember, if you have questions, Consult Your Pharmacist.

REFERENCES

1. Tremor fact sheet. National Institute of Neurological Disorders and Stroke. www.ninds.nih.gov/disorders/tremor/detail_tremor.htm. Accessed December 1, 2014.
2. Tremor. MedlinePlus. www.nlm.nih.gov/medlineplus/tremor.html. Accessed December 1, 2014.
3. Tremor. MedlinePlus. www.nlm.nih.gov/medlineplus/ency/article/003192.htm. Accessed December 1, 2014.
4. Hess CW, Pullman SL. Tremor: clinical phenomenology and assessment techniques. Tremor Other Hyperkinet Mov (N Y). 2012;2:PMC3517187. www.ncbi.nlm.nih.gov/pmc/articles/PMC3517187. Accessed December 1, 2014.
5. Essential tremor. Genetics Home Reference. http://ghr.nlm.nih.gov/condition/essential-tremor. Accessed December 1, 2014.
6. Essential tremor. PubMed Health. www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001768/. Accessed December 1, 2014.
7. Elble RJ. Essential tremor. Curr Neuropharmacol. 2013;11(1):48-52.
8. What is psychogenic movement? NINDS psychogenic movement information page. www.ninds.nih.gov/disorders/psychogenic_movement/psychogenic_movement.htm. Accessed December 1, 2014.
9. What is essential tremor? NINDS essential tremor information page. www.ninds.nih.gov/disorders/essential_tremor/essential_tremor.htm. Accessed December 1, 2014.

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