Summary of the more common neurologic manifestations of hyperthyroidism and Graves' disease

	Cardinal features	Relative frequency
Cognitive dysfunction	Ranges from mild inattention and anxiety to agitated delirium, rarely coma	Common, especially with acute and more severe thyrotoxicosis
Seizures	Usually generalized tonic-clonic seizures that usually occur with encephalopathy in acute thyrotoxicosis	Uncommon
Tremor	High frequency, low amplitude	Common
Chorea	Unifocal or multifocal, sustained or paroxysmal	Rare
Stroke	Usually cardioembolic, associated with thyrotoxic-induced atrial fibrillation	Rare
Myopathy	Usually mild proximal muscle weakness with normal serum CK	Common, but may be subclinical
Polyneuropathy	Usually an axonal sensory polyneuropathy Rare demyelinating polyneuropathy	Approximately 25 percent, but may be subclinical
Myasthenia gravis	Perhaps more likely to be ocular rather than generalized	Uncommon
Periodic paralysis	Usually associated with hypokalemia	Rare
Graves' ophthalmopathy	Proptosis, restricted eye movements	Approximately 25 percent of patients with Graves' disease

CK: creatine kinase.

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