Periodic paralysis - thyrotoxic
Thyrotoxic periodic paralysis involves attacks of muscle weakness or paralysis alternating with periods of normal muscle function. Attacks usually begin after symptoms of hyperthyroidism have developed.
The frequency of attacks varies from daily to yearly. Episodes of muscle weakness may last for a few hours or several days.
People are alert during attacks. Normal strength returns between attacks.
Symptoms of hyperthyroidism:
The health care provider may suspect thyrotoxic periodic paralysis based on:
Diagnosis involves ruling out disorders associated with low potassium.
The health care provider may attempt to trigger an attack by giving you insulin and glucose (which reduces potassium levels) or thyroid hormone.
During an attack, there may be the following signs:
Between attacks, examination is normal. Or, there may be signs of hyperthyroidism, such as an enlarged thyroid.
Hyperthyroidism is confirmed by abnormal results on the following tests:
Other test results:
A muscle biopsy may occasionally show abnormalities.
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