A Literature Review on Thyrotoxic Periodic Paralysis

Thyrotoxic periodic paralysis (TPP) is a rare disease of the muscles that presents with painless weakness of the muscles. The patients usually have hypokalemia and hyperthyroidism with elevations in the level of triiodothyronine (T3) and thyroxine (T4). The muscle weakness is usually transient, and the patients in many cases suffer from recurrent episodes of muscle paralysis. This flaccid muscle paralysis predominantly affects the proximal and lower extremities group of muscles more than the distal and upper extremity muscles. This condition is one of the drastic complications of Graves's disease and, unfortunately, may require admission and treatment in the critical care units. It is often not recognized during the initial attack in the American population as the prevalence is very low among the Caucasian population and people from North America. However, while the prevalence is extremely low in the Caucasian population, it is known to be 10 times more common among the Asian population when compared with the Caucasian population. Furthermore, while the diseases of the thyroid gland are more common in females, this rare disease predominantly affects male sex. It is treated by reversing the hypokalemia, which can in itself prove to be fatal if not corrected quickly, and this is followed by treatment to restore the euthyroid state. A literature review on this reversible cause of muscle weakness is very important to better understand this disease.