How is Thyrotoxic Periodic Paralysis Different from the Other Types of Primary Periodic Paralysis

There are several different types of primary periodic paralysis, including thyrotoxic periodic paralysis. All types of this condition have similar symptoms, but they all have different causes. The risk factors for all different types are the same and include hyperthyroidism and a family history of this condition. All types seem to have a genetic component, meaning that patients with any type of this condition most often have a family member that his this condition as well.

Thyrotoxic Periodic Paralysis

This type is rare and most often affects Asian men. It only affects patients with thyrotoxicosis, high levels of the thyroid hormone. In addition to the typical symptoms of this condition, patients with this type may experience other rare symptoms. These include difficulty swallowing, difficulty breathing, vision changes, speech difficulty.

Hypokalemic Periodic Paralysis

This type is most often present at birth. It differs from the other types because patients with this type will have normal levels of the thyroid hormone and normal thyroid function. Patients with this type will have very low blood-potassium levels during episodes.

Hyperkalemic Periodic Paralysis

This type is inherited and affects about one out of every 100,000 people. Men are affected more than women. Patients with this type will have high blood-levels of potassium during episodes. In some cases, the patient’s potassium level will be normal during episodes. Consuming potassium, even in small amounts, can trigger an episode.

Paramyotonia Congenita

This is considered a type by some, but it is most often associated with this condition because it sometimes occurs in patients who have the hyperkalemic type. This type is often longer-lasting than the other types, and on average lasts several days instead of 24 hours. Patients with this type may also experience pain, stiffness, and tightness in addition to weakness.

Andersen-Tawil Syndrome

This type is rare and was not recognized by the medical community until 1971. Patients with this type often experience irregular heart rhythms during episodes. Patients also often possess specific physical characteristics that are not present in the other types. These include fused or webbed toes (the 2nd and 3rd toes), widely spaced eyes that are large. Crooked toes or fingers, a small jaw, small stature, and low-set ears.


Kugler, M. R.N. (2006). Primary Periodic Paralysis Symptoms. Retrieved on October 26, 2009 from Website: