Neurological manifestations of thyrotoxicosis Although an extensive list of neurological presentations is beyond the scope of a short article about thyrotoxicosis, ischemic cerebrovascular disease of cardioembolic origin due to coexisting atrial fibrillation may be mentioned as one of the most serious complications of hyperthyroidism.

As to other autoimmune disorders related with thyrotoxicosis, an association between thyroid disease and myasthenia gravis has well been recognised. The thyroid disease, in this condition, is often an autoimmune one and approximately 5% of patients with myasthenia gravis also have hyperthyroidism. Especially, coexistence of ophthalmoplegia in a patient with hyperthyroidism may make the diagnosis even more difficult. Improvement with anticholinesterase therapy may not always point toward myasthenia gravis, since these drugs may also have beneficial effects on ophthalmoplegia due to hyperthyroidism. Thyroid function tests are, therefore, warranted for cases with myasthenia gravis. Myasthenia rarely improves after thyroid treatment and relation between two entities is yet unknown.

Some very rare neurological manifestations that are reported to be dubiously associated with thyrotoxicosis are pseudotumor cerebri, amyotrophic lateral sclerosis and a Guillain-Barré like syndrome.