Laboratory work-up is not necessary for most patients with suspected essential tremor because diagnosis is based on careful medical history and phys ical examination. When indicated, laboratory assess ment includes tests of thyroid function and diagnostic studies to exclude Wilson’s disease. In a patient with postural or kinetic tremor who is younger than 40 years, serum ceruloplasmin can be used to investigate the presence of Wilson’s disease—a neurological disorder that can manifest as postural tremor. 1 Imaging of striatal dopamine transporters might distinguish patients with essential tremor from those with Parkinson’s disease: the latter have lower concentrations of striatal dopamine transporter than do patients with essential tremor or controls. 1 Quantitative computerised analysis of tremor is available in some tertiary-care facilities, and might guide the clinician to distinguish essential tremor from enhanced physiological tremor. 1 Essential tremor is a progressive disorder, and predictors of progression include asymmetrical tremor and unilateral onset of the initial tremor. 4 Tremor can cause functional disability and decrease quality of life. 5 For instance, cognition and personality might be affected. 5, 6 Drug therapy generally starts when the tremor begins to affect the patient’s ability to do daily activities or when the tremor becomes embarrassing. 1 A caveat for clinicians who start antitremor treatment is to “start low and go slow” to reduce adverse drug events and to increase patients’ tolerance. 1 If there is no benefit, treatment should be decreased progressively and discontinued. If the benefit is only partial, a second drug can be added and slowly increased until adequate benefit is achieved or until the maximum attainable dose is reached. 1 Patients who need only intermittent tremor reduction (eg, for attendance at a social event) might benefit from taking 10–40 mg oral propranolol about 30 min before the event. 1 Surgery should be limited to patients with disabling essential tremor that does not respond to drugs. 1 Propranolol and primidone are effective for 30–70% of patients. Propranolol, which acts mainly on the peripheral nervous system, might reduce tremor amplitude at daily doses of 120 mg or higher. 7 The anticonvulsant primidone has shown efficacy in placebo-controlled trials at doses of up to 750 mg a day. 8 However, tolerability is an issue with primidone, even at low starting doses: about 20% of patients stop treatment with primidone because of the most common side-effects of drowsiness and unsteadiness. 8 Efficacy does not differ significantly between propranolol and primidone, 9 although primidone might be more tolerable in the long term than propranolol. 10 Various other oral agents are used to treat essential tremor, with a range of efficacy (table). 1, 11 Of these, other β-adrenergic receptor antagonists such as atenolol and sotalol might reduce tremor. 12 Alprazolam, a benzodiazepine, might help reduce essential tremor. 13 A well-designed multicentre, double-blind, randomised trial found that topiramate (up to maximum tolerated dose of 400 mg a day or dose at which tremor resolved) was more effective than placebo in the treatment of essential tremor. 14 Gabapentin, 15 an anticonvulsant, has shown efficacy in some clinical trials, but not others. At single doses of 40–400 U, botulinum A toxin may alleviate neck tremor (oral drugs are less useful for treatment of neck tremor than arm tremor), 1, 11 and at doses of 50–100 U injected into arm muscle, it is modestly effective for treatment of hand tremor (extensor finger weakness might occur, although a reduced dose to the extensors usually prevents this adverse effect). 11, 16 The …