A 51-year-old man presents for his annual wellness visit with his primary care physician. His wife has noticed a tremor while he is working on his car and knows that his father died of Parkinson disease. He says that the tremor is nothing to worry about and only occurs during a few activities such as pouring drinks, pointing the remote at the television, or fixing his car. The patient states his wife is just overreacting. His medical problems include hypertension, diabetes, and hyperlipidemia for which he takes lisinopril, metformin, and atorvastatin. He has 3-5 drinks of scotch per night before working on his car. On physical exam, the tremor is replicated during finger to nose testing. Romberg sign is negative. Cranial nerves II-XII are intact. The rest of the exam is benign. Which of the following is the most appropriate treatment for this patient's tremor?
Alcoholics anonymous
Aripiprazole
Phenobarbital
Propranolol
Propranolol
This patient who presents with a tremor that only occurs during terminal activity and is likely improved by alcohol (hence why he drinks prior to working on the car) has benign essential tremor. This is best treated with propranolol.

Benign essential tremor is a type of rhythmic oscillatory movement that occurs with posturing and action. The pathophysiology of this disorder is unclear; however, it classically gets worse with actions that require terminal positioning of the extremities such as pouring a drink or pointing a television remote. The tremor improves with alcohol consumption so patients will often self-medicate with alcoholic drinks. There is a strong genetic component, with an autosomal dominant pattern of inheritance with incomplete penetrance. The best method of replicating the tremor is with the finger-nose-finger test because this requires the patient to perform a precise activity at a terminal distance. The diagnosis is made clinically. Treatment is with propranolol or primidone, which are both considered first-line agents although the latter has less evidence for its efficacy.

Paparella et al. studied the effects of propranolol on head and upper extremity movements in patients with benign essential tremors. They found that this medication has no effect on head movements but reduces the number of upper extremity tremors in these patients. They recommended that agents other than propranolol should be used for the treatment of head tremors in these patients.

Incorrect Answers:
Answer A: Alcoholics anonymous is the first-line treatment for patients with alcohol use disorder; however, the tremors that occur during alcohol withdrawal are not isolated to movements during terminal activities. Alcohol withdrawal also presents with other signs including restlessness, diaphoresis, and insomnia. More severe cases can present with hallucinations and seizures. The response of this patient's tremor to alcohol consumption is typical of patients with benign essential tremor.

Answer B: Aripiprazole and other atypical antipsychotic medications can be used in patients with Tourette syndrome; however, these patients will present with involuntary tics rather than a tremor that only occurs during a voluntary activity at the terminal range of motion. Moreover, for the diagnosis of Tourette syndrome, both motor and phonic tics must be present.

Answer C: Carbidopa can be used in the treatment of Parkinson disease; however, the tremor associated with this disease classically occurs at rest and is described in character as a "pill-rolling" tremor. The other features of Parkinson disease include bradykinesia or akinesia, rigidity, and postural instability.

Answer D: Phenobarbital can be used in the treatment of Huntington disease; however, the involuntary movements seen in this disease are classically choreiform rather than intention tremor. Huntington disease presents with chorea, psychiatric illness, and depression. There is commonly a strong genetic predisposition, as it is a trinucleotide repeat disorder that exhibits anticipation.

Bullet Summary:
Propranolol can be used in the treatment of patients with benign essential tremor, which presents with an action tremor that is alleviated by alcohol use.