Periodic family paralysis - the hereditary disease, described suddenly coming transient attacks of a flaccid paralysis of extremities.

Etiology, pathogenesis. The reason of disease is unknown. In a basis of a pathogenesis passing disturbance of a level of a potassium in a blood lays.

Signs, current. The first attacks of muscular delicacy appear in the childhood or young age. In most cases the attack begins in the early morning. Paralyses of muscles usually reach a maximum within an hour, symmetrically grasp extremities (mainly proximal departments); delicacy only the bottom extremities is sometimes observed. Bulbar, oculomotor and respiratory muscles usually are not involved in process. Paralyses flaccid, with a hypotension and an areflexia. Sensitivity is kept. The consciousness is not broken. Typically appreciable depression of a level of a potassium in a blood. The paralysis lasts from several minutes till several o'clock. In the period between attacks suffering this paralysis are practically healthy. Thus, it is possible to consider disease good-quality. Only in very rare cases involving in process of a respiratory musculation can lead to mors.