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Not all individuals with ET require treatment, but there are many treatment options depending on symptom severity. Caffeine and stress should be avoided, and good sleep is recommended.
When symptoms are sufficiently troublesome to warrant treatment, the first medication choices are beta blockers such as propranolol or alternately, nadolol and timolol. Atenolol and pindolol are not effective for tremor. The anti-epileptic primidone is also effective for ET.
Second-line or third-line medications can be added if the first-line medications do not control the tremor. Second-line medications are the anti-epileptics topiramate, gabapentin (as monotherapy) and levetiracetam, or benzodiazepines like alprazolam. Third-line medications are clozapine and mirtazapine.
Theophylline has been used by some practitioners to treat ET, even though it may also induce tremor. However, its use is debated due to conflicting data on its efficacy. There is some evidence that low doses may lead to improvement.
Ethanol has shown superior efficacy to that of benzodiazepines in small trials. It improves tremor in small doses and its effects are usually noticeable within 20 minutes for 3–5 hours, but occasionally appears a rebound tremor augmentation later.
When medications do not control the tremor or the person does not tolerate medication, botulinum toxin, deep brain stimulation or occupational therapy can be helpful. The electrodes for deep brain stimulation are usually placed in the "tremor center" of the brain, the ventral intermediate nucleus of the thalamus.
Additionally, MRI-guided high intensity focused ultrasound is a non-surgical treatment option for people with essential tremor who have not seen improvement with medication and refused or are not valid candidates for other techniques, such as deep brain stimulation. MRI-guided high intensity focused ultrasound does not achieve healing but can improve the quality of life. However, its safety, efficacy and long-term effects are not yet established. Temporary and permanent adverse side effects have been documented, and also the reappearance of tremors. Possible adverse events include gait difficulties, balance disturbances, paresthesias, headache, hemorrhage in the treated area (which requiries emergency treatment), tissue damage in other areas, skin burns with ulcerations, skin retraction, scars and blood clots. This procedure is contraindicated in pregnant women, persons who have a non-MRI compatible implanted metallic devices, allergy to MR contrast agents, cerebrovascular disease, abnormal bleeding, hemorrhage and/or blood clotting disorders, advanced kidney disease or on dialysis, heart conditions, severe hypertension, ethanol or substance abuse, among others. The US Food and Drug Administration ("FDA") approved Insightec’s Exablate Neuro system to treat essential tremor in 2016.
Although essential tremor is often mild, people with severe tremor have difficulty performing many of their routine activities of daily living. ET is generally progressive in most cases (sometimes rapidly, sometimes very slowly), and can be disabling in severe cases.
Before prescribing medication for these conditions which often resolve spontaneously, recommendations have pointed to improved skin hygiene, good hydration via fluids, good nutrition, and installation of padded bed rails with use of proper mattresses. Pharmacological treatments include the typical neuroleptic agents such as fluphenazine, pimozide, haloperidol and perphenazine which block dopamine receptors; these are the first line of treatment for hemiballismus. Quetiapine, sulpiride and olanzapine, the atypical neuroleptic agents, are less likely to yield drug-induced parkinsonism and tardive dyskinesia. Tetrabenazine works by depleting presynaptic dopamine and blocking postsynaptic dopamine receptors, while reserpine depletes the presynaptic catecholamine and serotonin stores; both of these drugs treat hemiballismus successfully but may cause depression, hypotension and parkinsonism. Sodium valproate and clonazepam have been successful in a limited number of cases. Stereotactic ventral intermediate thalamotomy and use of a thalamic stimulator have been shown to be effective in treating these conditions.
The medical treatment of essential tremor at the Movement Disorders Clinic at Baylor College of Medicine begins with minimizing stress and tremorgenic drugs along with recommending a restricted intake of beverages containing caffeine as a precaution, although caffeine has not been shown to significantly intensify the presentation of essential tremor. Alcohol amounting to a blood concentration of only 0.3% has been shown to reduce the amplitude of essential tremor in two-thirds of patients; for this reason it may be used as a prophylactic treatment before events during which one would be embarrassed by the tremor presenting itself. Using alcohol regularly and/or in excess to treat tremors is highly unadvisable, as there is a purported correlation between tremor and alcoholism. Alcohol is thought to stabilize neuronal membranes via potentiation of GABA receptor-mediated chloride influx. It has been demonstrated in essential tremor animal models that the food additive 1-octanol suppresses tremors induced by harmaline, and decreases the amplitude of essential tremor for about 90 minutes.
Two of the most valuable drug treatments for essential tremor are propranolol, a beta blocker, and primidone, an anticonvulsant. Propranolol is much more effective for hand tremor than head and voice tremor. Some beta-adrenergic blockers (beta blockers) are not lipid-soluble and therefore cannot cross the blood–brain barrier (propranolol being an exception), but can still act against tremors; this indicates that this drug’s mechanism of therapy may be influenced by peripheral beta-adrenergic receptors. Primidone’s mechanism of tremor prevention has been shown significantly in controlled clinical studies. The benzodiazepine drugs such as diazepam and barbiturates have been shown to reduce presentation of several types of tremor, including the essential variety. Controlled clinical trials of gabapentin yielded mixed results in efficacy against essential tremor while topiramate was shown to be effective in a larger double-blind controlled study, resulting in both lower Fahn-Tolosa-Marin tremor scale ratings and better function and disability as compared to placebo.
It has been shown in two double-blind controlled studies that injection of botulinum toxin into muscles used to produce oscillatory movements of essential tremors, such as forearm, wrist and finger flexors, may decrease the amplitude of hand tremor for approximately three months and that injections of the toxin may reduce essential tremor presenting in the head and voice. The toxin also may help tremor causing difficulty in writing, although properly adapted writing devices may be more efficient. Due to high incidence of side effects, use of botulinum toxin has only received a C level of support from the scientific community.
Deep brain stimulation toward the ventral intermediate nucleus of the thalamus and potentially the subthalamic nucleus and caudal zona incerta nucleus have been shown to reduce tremor in numerous studies. That toward the ventral intermediate nucleus of the thalamus has been shown to reduce contralateral and some ipsilateral tremor along with tremors of the cerebellar outflow, head, resting state and those related to hand tasks; however, the treatment has been shown to induce difficulty articulating thoughts (dysarthria), and loss of coordination and balance in long-term studies. Motor cortex stimulation is another option shown to be viable in numerous clinical trials.
Medications remain the basis of therapy in many cases. Symptomatic drug therapy is available for several forms of tremor:
- Parkinsonian tremor drug treatment involves L-DOPA and/or dopamine-like drugs such as pergolide, bromocriptine and ropinirole; They can be dangerous, however, as they may cause symptoms such as tardive dyskinesia, akathisia, clonus, and in rare instances tardive (late developing) psychosis. Other drugs used to lessen parkinsonian tremor include amantadine and anticholinergic drugs like benztropine
- Essential tremor may be treated with beta blockers (such as propranolol and nadolol) or primidone, an anticonvulsant
- Cerebellar tremor symptoms may decrease with the application of alcohol (ethanol) or benzodiazepine medications, both of which carry some risk of dependence and/or addiction
- Rubral tremor patients may receive some relief using L-DOPA or anticholinergic drugs. Surgery may be helpful
- Dystonic tremor may respond to diazepam, anticholinergic drugs, and intramuscular injections of botulinum toxin. Botulinum toxin is also prescribed to treat voice and head tremors and several movement disorders
- Primary orthostatic tremor sometimes is treated with a combination of diazepam and primidone. Gabapentin provides relief in some cases
- Enhanced physiological tremor is usually reversible once the cause is corrected. If symptomatic treatment is needed, beta blockers can be used
There is no cure for most tremors. The appropriate treatment depends on accurate diagnosis of the cause. Some tremors respond to treatment of the underlying condition. For example, in some cases of psychogenic tremor, treating the patient’s underlying psychological problem may cause the tremor to disappear. A few medications can help relieve symptoms temporarily.
It is very difficult to treat an intention tremor. The tremor may disappear for a while after a treatment has been administered and then return. This situation is addressed with a different treatment. First, individuals will be asked if they use any of the drugs known to cause tremors. If so, they are asked to stop taking the medication and then evaluated after some time to determine if the medication was related to the onset of the tremor. If the tremor persists, treatment that follows may include drug therapy, lifestyle changes, and more invasive forms of treatment, such as surgery and thalamic deep brain stimulation.
Intention tremors are known to be very difficult to treat with pharmacotherapy and drugs. Although there is no established pharmacological treatment for an intention tremor, several drugs have been found to have positive effects on intention tremors and are used as treatment by many health professionals. Isoniazid, buspirone hydrochloride, glutethimide, carbamazepine, clonazepam, topiramate, zofran, propranolol and primidone have all seen moderate results in treating intention tremor and can be prescribed treatments. Isoniazid inhibits γ-aminobutyric acid-aminotransferase, which the first step in enzymatic breakdown of GABA, thus increasing GABA, the major inhibitory neurotransmitter in the central nervous system. This causes a reduction in cerebellar ataxias. Another neurotransmitter targeted by drugs that has been found to alleviate intention tremors is serotonin. The agonist buspirone hydrochloride, which decreases serotonin's function in the central nervous system, has been viewed as an effective treatment of intention tremors.
Physical therapy has had great results in reducing tremors but usually does not cure them. Relaxation techniques, such as meditation, yoga, hypnosis, and biofeedback, have seen some results with tremors. Wearing wrist weights which weigh down one's hands as they make movements, masking much of the tremor, is a proven home remedy. This is not a treatment, since wearing the weights does not have any lasting effects when they are not on. However, they do help the individual cope with the tremor immediately.
A more radical treatment that is used in individuals who do not respond to drug therapy, physical therapy, or any other treatment listed above, with moderate to severe intention tremors, is surgical intervention. Deep brain stimulation and surgical lesioning of the thalamic nuclei has been found to be an effective long-term treatment with intention tremors.
Deep brain stimulation treats intention tremors but does not help related diseases or disorders such as dyssynergia and dysmetria. Deep brain stimulation involves the implantation of a device called a neurostimulator, sometimes called a 'brain pacemaker'. It sends electrical impulses to specific parts of the brain, changing brain activity in a controlled manner. In the case of an intention tremor, the thalamic nuclei is the region targeted for treatment. This form of treatment causes reversible changes and does not cause any permanent lesions. Since it is reversible, deep brain stimulation is considered fairly safe: Reduction in tremor amplitude is almost guaranteed and sometimes resolved. Some individuals with multiple sclerosis have seen sustained benefits in MS progress.
Thalamotomy is another surgical treatment where lesions of the thalamus nucleus are created to disrupt the tremor circuit. Thalamotomy has been used to treat many forms of tremors, including those that arise from trauma, multiple sclerosis, stroke, and those whose cause it unknown. This is a very invasive, high-risk treatment with many negative effects, such as multiple sclerosis worsening, cognitive dysfunction, worsening of dysarthria, and dysphagia. Immediate positive effects are seen in individuals treated with a thalamotomy procedure. However, the tremor often comes back; it is not a complete treatment. Thalamotomy is in clinical trials to determine the validity of the treatment of intention tremors with all its high risks.
Research has focused on finding a pharmacological treatment that is specific for intention tremor. Limited success has been seen in treating intention tremor with drugs effective at treating essential tremor. Clinical trials of levetiracetam, typically used to treat epilepsy, and pramipexole, used to treat resting tremor, were completed in 2009-2010 to establish their effectiveness in treating kinetic tremor. A clinical trial for riluzole, typically used to treat amyotrophic lateral sclerosis, was completed at the Sapienza University of Rome to evaluate its effectiveness of treating cerebellar ataxia and kinetic tremor.
Treatment of a Holmes tremor can fail or is delayed because there are only a few diagnostic tools available. The treatment of choice is complete removal of the tumor. Removing the tumor can result in elimination or better control of the tremors. Other treatment options involve coping strategies such as avoiding movements or actions that worsen tremors. Patients suffering from Holmes tremors can also benefit from using larger utensil handles and wrist weights. There are also some pharmacological treatments, but they are not very effective.
Risk factors for Holmes tremor include excess exposure to heavy metals, such as mercury and lead, as well as an increased intake of various drugs and toxins. Researchers found that raising the dose of antidepressants or neuroleptics elevate the risk for developing Holmes tremor. Increasing intake of coffee, tea, or other stimulants can also cause for greater risk of development. Tremors depend on dosage and amount of exposure to these factors and will typically decrease dramatically if the intake is reduced. Hyperthyroidism and hyperglycemia also increase the likelihood of developing Holmes tremor.
Dopaminergic drugs are commonly used in the early stages of the hypokinesia to treat patients. With increased intake, though, they can become ineffective because of the development of noradrenergic lesions. While initially the dopaminergic drugs may be effective, these noradrenergic lesions are associated with hypokinesic gait disorder development later on.
Some Parkinson's patients are unable to move during sleep, prompting the diagnosis of "nocturnal hypokinesia". Physicians have experienced success treating this sleep disorder with slow-release or night-time dopaminergic drugs, and in some cases, continuous stimulation by the dopamine agonist rotigotine. Despite improved mobility during sleep, many Parkinson's patients report an extremely uncomfortable sleeping experience even after dopaminergic treatments.
In the past, dopamine blocking agents have been used in the treatment of spasmodic torticollis. Treatment was based on the theory that there is an imbalance of the neurotransmitter dopamine in the basal ganglia. These drugs have fallen out of fashion due to various serious side effects: sedation, parkinsonism, and tardive dyskinesia.
Other oral medications can be used in low doses to treat early stages of spasmodic torticollis. Relief from spasmodic torticollis is higher in those patients who take anticholinergic agents when compared to other oral medications. Many have reported complete management with gabapentin alone or in combination with another drug such as clonazepam. 50% of patients who use anticholinergic agents report relief, 21% of patients report relief from clonazepam, 11% of patients report relief from baclofen, and 13% from other benzodiazepines.
Higher doses of these medications can be used for later stages of spasmodic torticollis; however, the frequency and severity of side effects associated with the medications are usually not tolerated. Side effects include dry mouth, cognitive disturbance, drowsiness, diplopia, glaucoma and urinary retention.
Methylphenidate, commonly used to treat ADHD, has been used in conjunction with levodopa to treat hypokinesia in the short term. The two work together to increase dopamine levels in the striatum and prefrontal cortex. Methylphenidate mainly inhibits dopamine and noradrenaline reuptake by blocking presynaptic transporters, and levodopa increases the amount of dopamine, generally improving hypokinesic gait. Some patients, however, have adverse reactions of nausea and headache to the treatment and the long-term effects of the drug treatment still need to be assessed.
The most commonly used treatment for spasmodic torticollis is the use of botulinum toxin injection in the dystonic musculature. Botulinum toxin type A is most often used; it prevents the release of acetylcholine from the presynaptic axon of the motor end plate, paralyzing the dystonic muscle. By disabling the movement of the antagonist muscle, the agonist muscle is allowed to move freely. With botulinum toxin injections, patients experience relief from spasmodic torticollis for approximately 12 to 16 weeks. There are several type A preparations available worldwide; however Botox and Dysport are the only preparations approved by the U.S. Food and Drug Administration (FDA) for clinical use in the United States.
Some patients experience or develop immunoresistance to botulinum toxin type A and must use botulinum toxin type B. Approximately 4% to 17% of patients develop botulinum toxin type A antibodies. The only botulinum toxin type B accessible in the United States is Myobloc. Treatment using botulinum toxin type B is comparable to type A, with an increased frequency of the side effect dry mouth.
Common side effects include pain at the injection site (up to 28%), dysphagia due to the spread to adjacent muscles (11% to 40%), dry mouth (up to 33%), fatigue (up to 17%), and weakness of the injected or adjacent muscle (up to 56%). A Cochrane review published in 2016 reported moderate-quality evidence that a single Botulinum toxin-B treatment session could improve cervical dystonia symptoms by 10% to 20%, although with an increased risk of dry mouth and swallowing difficulties.
In some cases Meige's syndrome can be reversed when it is caused by medication. It has been theorized that it is related to cranio-mandibular orthopedic misalignment, a condition that has been shown to cause a number of other movement disorders (Parkinon's, tourettes, and torticollis). This theory is supported by the fact that the trigeminal nerve is sensory for blink reflex, and becomes hypertonic with craniomandibular dysfunction. Palliative treatments are available, such as botulinum toxin injections.
Parkinsonism is a clinical syndrome characterized by tremor, bradykinesia, rigidity, and postural instability. Parkinsonism is found in Parkinson's disease (after which it is named), however a wide range of other causes may lead to this set of symptoms, including some toxins, a few metabolic diseases, and a handful of neurological conditions other than Parkinson's disease.
About 7% of people with parkinsonism have developed their symptoms following treatment with particular medications. Side effect of medications, mainly neuroleptic antipsychotics especially the phenothiazines (such as perphenazine and chlorpromazine), thioxanthenes (such as flupenthixol and zuclopenthixol) and butyrophenones (such as haloperidol), piperazines (such as ziprasidone), and rarely, antidepressants. The incidence of drug-induced parkinsonism increases with age. Drug-induced parkinsonism tends to remain at its presenting level, not progress like Parkinson's disease.
Some degree of control of the fasciculations may be achieved with the same medication used to treat essential tremor (beta-blockers and anti-seizure drugs). However, often the most effective approach to treatment is to treat any accompanying anxiety. No drugs, supplements, or other treatments have been found that completely control the symptoms. In cases where fasciculations are caused by magnesium deficiency, supplementing magnesium can be effective in reducing symptoms.
In many cases, the severity of BFS symptoms can be significantly reduced through a proactive approach to decrease the overall daily stress. Common ways to reduce stress include: exercising more, sleeping more, working less, meditation, and eliminating all forms of dietary caffeine (e.g. coffee, chocolate, cola, and certain over-the counter medications).
If pain or muscle aches are present alongside fasciculations, patients may be advised to take over-the-counter pain medications such as ibuprofen or acetaminophen during times of increased pain. Other forms of pain management may also be employed. Prior to taking any over-the-counter medications, individuals should initiate discussions with their health care provider(s) to avoid adverse effects associated with long-term usage or preexisting conditions.
The prognosis for those suffering from diagnosed benign fasciculation syndrome is generally regarded as being good to excellent. The syndrome causes no known long-term physical damage. Patients may suffer elevated anxiety even after being diagnosed with the benign condition. Such patients are often directed towards professionals who can assist with reductions and understanding of stress/anxiety, or those who can prescribe medication to help keep anxiety under control.
Spontaneous remission has been known to occur, and in cases where anxiety is thought to be a major contributor, symptoms are typically lessened after the underlying anxiety is treated. In a 1993 study by Mayo Clinic, 121 individuals diagnosed with benign fasciculation syndrome were assessed 2–32 years (~7 years average) after diagnosis. Of those patients there were no cases of BFS progressing to a more serious illness, and 50% of the patients reported significant improvement in their symptoms at the time of the follow-up. Only 4% of the patients reported symptoms being worse than those present at the time of their diagnosis.
Treatment of Ramsay Hunt Syndrome Type 1 is specific to individual symptoms. Myoclonus and seizures may be treated with drugs like valproate.
Some have described this condition as difficult to characterize.
Parkinson-plus syndromes are usually more rapidly progressive and less likely to respond to antiparkinsonian medication than PD. However, the additional features of the diseases may respond to medications not used in PD.
Current therapy for Parkinson-plus syndromes is centered around a multidisciplinary treatment of symptoms.
These disorders have been linked to pesticide exposure.
There is no cure for XDP and medical treatment offers only temporary relief. Some authors have reported benzodiazepines and anticholinergic agents in the early stages of the disease. Botulinum toxin injections have been used to relieve focal dystonia. Deep brain stimulation has shown promise in the few cases treated surgically.
Differentiating some kinds of atypical Parkinson: Northwest Parkinson Foundation
Before Parkinson's disease is diagnosed, the differential diagnoses include:
- AIDS can sometimes lead to the symptoms of secondary parkinsonism, due to commonly causing dopaminergic dysfunction. Indeed, parkinsonism can be a presenting feature of HIV infection.
- Corticobasal degeneration
- Creutzfeldt–Jakob disease
- Dementia pugilistica or "boxer's dementia" is a condition that occurs in athletes due to chronic brain trauma.
- Diffuse Lewy body disease
- Drug-induced parkinsonism ("pseudoparkinsonism") due to drugs such as antipsychotics, metoclopramide, sertraline, fluoxetine or the toxin MPTP
- Encephalitis lethargica
- Essential tremor, an illness which has some diagnostic overlap with Parkinson's disease
- Orthostatic tremor
- MDMA addiction and frequent use has been linked to Parkonsonism. Several cases have been reported where individuals are diagnosed with the syndrome after taking MDMA.
- Multiple system atrophy
- Pantothenate kinase-associated neurodegeneration, also known as neurodegeneration with brain iron accumulation or Hallervorden-Spatz syndrome
- Parkinson plus syndrome
- Progressive supranuclear palsy
- Toxicity due to substances such as carbon monoxide, carbon disulfide, manganese, paraquat, mercury, hexane, rotenone, Annonaceae, and toluene (inhalant abuse: "huffing")
- Vascular parkinsonism, associated with underlying cerebrovascular disease
- Wilson's disease is a genetic disorder in which an abnormal accumulation of copper occurs. The excess copper can lead to the formation of a copper-dopamine complex, which leads to the oxidation of dopamine to aminochrome. The most common manifestations include bradykinesia, cogwheel rigidity and a lack of balance.
- Paraneoplastic syndrome: neurological symptoms caused by antibodies associated with cancers
- Genetic
- Rapid onset dystonia parkinsonism
- Parkin mutation
- X-linked dystonia parkinsonism
- Autosomal recessive juvenile parkinsonism
Several dopamine agonists that bind to dopamine receptors in the brain have similar effects to levodopa. These were initially used as a complementary therapy to levodopa for individuals experiencing levodopa complications (on-off fluctuations and dyskinesias); they are now mainly used on their own as first therapy for the motor symptoms of PD with the aim of delaying the initiation of levodopa therapy and so delaying the onset of levodopa's complications. Dopamine agonists include bromocriptine, pergolide, pramipexole, ropinirole, piribedil, cabergoline, apomorphine and lisuride.
Though dopamine agonists are less effective than levodopa at controlling PD motor symptoms, they are usually effective enough to manage these symptoms in the first years of treatment. Dyskinesias due to dopamine agonists are rare in younger people who have PD but, along with other complications, become more common with older age at onset. Thus dopamine agonists are the preferred initial treatment for younger onset PD, and levodopa is preferred for older onset PD.
Dopamine agonists produce significant, although usually mild, side effects including drowsiness, hallucinations, insomnia, nausea, and constipation. Sometimes side effects appear even at a minimal clinically effective dose, leading the physician to search for a different drug. Agonists have been related to impulse control disorders (such as compulsive sexual activity, eating, gambling and shopping) even more strongly than levodopa. They tend to be more expensive than levodopa.
Apomorphine, a non-orally administered dopamine agonist, may be used to reduce off periods and dyskinesia in late PD. It is administered by intermittent injections or continuous subcutaneous infusions. Since secondary effects such as confusion and hallucinations are common, individuals receiving apomorphine treatment should be closely monitored. Two dopamine agonists that are administered through skin patches (lisuride and rotigotine) and are useful for people in the initial stages and possibly to control off states in those in the advanced state.
Exercise in middle age may reduce the risk of Parkinson's disease later in life. Caffeine also appears protective with a greater decrease in risk occurring with a larger intake of caffeinated beverages such as coffee. People who smoke cigarettes or use smokeless tobacco are less likely than non-smokers to develop PD, and the more they have used tobacco, the less likely they are to develop PD. It is not known what underlies this effect. Tobacco use may actually protect against PD, or it may be that an unknown factor both increases the risk of PD and causes an aversion to tobacco or makes it easier to quit using tobacco.
Antioxidants, such as vitamins C and E, have been proposed to protect against the disease, but results of studies have been contradictory and no positive effect has been proven. The results regarding fat and fatty acids have been contradictory, with various studies reporting protective effects, risk-increasing effects or no effects. There have been preliminary indications that the use of anti-inflammatory drugs and calcium channel blockers may be protective. A 2010 meta-analysis found that nonsteroidal anti-inflammatory drugs (apart from aspirin), have been associated with at least a 15 percent (higher in long-term and regular users) reduction of incidence of the development of Parkinson's disease.
It is named for James Ramsay Hunt who first described a form of progressive cerebellar dyssynergia associated with myoclonic epilepsy in 1921.