User:P.Phan!pharmd26/Essential tremor

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Treatment

Patients with mild tremor that does not interfere with daily activities and psychological well-being does not require pharmacological treatments. Patients with persistent tremor which impacts daily functions should be treated with the appropriate pharmacological therapies.

Non-pharmacological Treatment

The first approach in helping patients to improve tremor's symptoms is discontinuation of triggering and exacerbating factors like medications including certain antidepressants, anti-epileptics, beta agonists; or substances like caffeine. In addition, getting adequate sleep and utilizing relaxation techniques can also help improve and reduce tremor's symptoms in patients which reported increased in tremor following physical activities.

Since tremor can affects different part of the body (like limbs, head, chin/jaw, vocal), different non-pharmacological therapeutic techniques are available which can support patients with the management of tremor including occupational therapy, speech therapy, and psychotherapy. Occupational therapy provide supports to help patients to manage everyday tasks easier through different approaches and interventions. Speech therapy is helpful in patients with vocal tremor to help manage and maintain the vocal changes associated with tremor symptoms. Psychological impacts like embarrassment and anxiety are also important concerns of many patient with ET which can lead to social isolation and depression. Psychotherapy can be very beneficial and play a key role in helping patients to improve mental health of ET patients.

Alcohol

Alcohol had been known to help provide short term relieve of tremor symptoms in some patients, however, therapeutic of effects of alcohol on ET had not ben studied in many clinical trials. It had been proposed that alcohol can help reduce tremor through the agonism mechanism of the gamma-aminobutyric acid GABAergic. Since GABA can decrease the neural activity, so it is believed that alcohol can increased the activity of GABA which then can reduce involuntary muscle movements or tremors. However, the duration of action of alcohol on ET is around 3-4 hours, alcohol also had been associated with rebound of tremor, not to mention the risk of development of long-term alcohol consumption and abuse. The use of alcohol as a possible treatment for ET is not recommended by healthcare providers.

Pharmacological Treatments

Currently, The available pharmacological therapies options for ET are Beta-adrenergic blockers, Anticonvulsants, Benzodiazepines/GABAergic agents, Calcium channel blockers, Atypical neuroleptic agents. The two most effective medications which had been approved by FDA as first line agents for the treatment of ET are propranolol and primidone.

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Beta-adrenergic blockers

[edit] When symptoms are sufficiently troublesome to warrant treatment, the first choice medication is propranolol, a non-selective beta-blocker, which had been shown effective in reduction tremor by 70% in 50% patients in clinical studies. Based on the guidelines from the American Acedamy of Neurology and the Italian Movement Disorders Association, propranolol is most effective in limbs tremors, also there is little to no effect on head tremors. The recommended doses of propranolol is ranging from 60 to 360 mg daily, and it is based on patient's specific factors. The common reported side effects of propranolol are bradycardia, bronchospasm, fatigue, hypotension. In patients that have contraindicated comorbidities to propranolol, other beta blockers such as Atenolol, pindolol,Sotalol, and nadolol have shown some potential efficacy, but they are not very well studies and have limited evidence in their efficacy on the treatment of ET.

Anticonvulsants

Primidone is another first line agent recommended in the treatment of ET. Primidone is an anticonvulsants which metabolized into phenobarbital and phenylethymalnonamide. This medication had shown the same beneficial effects in reduction tremors as propranolol and is recommended to use based on guidelines from the American Academy of Neurology and the MDS Task Force on Tremor. The initial dose of primidone is recommended at 25 mg per day, and should be increased up to the maximum dose of 250 mg per day. This strategy was recommended to help avoid the possible side effects of nausea, vomiting, and excessive sedation of primidone. Primidone is the preferred medication for treatment of ET in geriatric population compared to propranolol. In addition, Combination therapy of both Propranolol and Primidone is recommended for patients that do not shown benefits from either propranolol or primidone as monotherapy.

Topiramate is an antiepileptic medication which had been studied to assess the efficacy and safety in the treatment of ET. Overall, it is considered as a second-line therapy alone or in combination with other medications when first-line treatments fail to shown improvement or medication intolerance. Topiramate shown effective in reducing limb tremors at the maximum dose of 200 mg, however there were higher risk for development of adverse effects included weight loss, anorexia, cognitive impairment, and kidney stone.

Other second-line medications

[edit] Additional medications had been reported to shown efficacy in treating ET are gabapentin, benzodiazepines such as alprazolam, clonazepam, and zonisamide, pregabalin. However, most of the medication have limited evidence-based to support their clinical usage as treatments for ET. Some systematic reviews of medications for the treatment of ET have been conducted. A 2017 review of topiramate found limited data and low-quality evidence to support its efficacy and the occurrence of treatment-limiting adverse effects, a 2017 review of zonisamide found insufficient information to assess efficacy and safety, and a 2016 review of pregabalin determined the effects to be uncertain due to the low quality of evidence.

Botulinum Toxin (BoNT)

Botulinum toxin is neurotoxin produced by a gram positive, rod-shaped bacteria called Clostridium botulinum. BoNT works by inhibiting acetylcholine release at the presynaptic terminal by inactivating the SNARE proteins, which interfere with muscle contraction. BoNT type A injections have shown benefits in several clinical trials for the treatments of limb, voice, and head. However, the associated side effects included muscle weakness, stiffness were reported with in studies of limb tremors, and neck muscle pain, weakness, and dysphagia in clinical trials of head tremors.

Deep Brain Stimulation (DBS)

Another invasive surgical treatment of essential tremor is deep brain stimulation (DBS). DBS is a surgical procedure involves the placement of permanent electrode with 4-8 contacts within the brain with connecting wire connected to a stimulator implanted near the patients' collar bone. Electrical impulses travel from the stimulator to the target areas within the brain which can affects cells and chemical activities of the brain. At one year followed the surgical intervention with DBS, patients shown 66% improvement, and 48% improvement at 10 years. Despite new techniques are being developed for the treatment of ET, DBS is still consider the best surgical intervention for essential tremor.