Hypokalemic periodic paralysis is a disorder related to periodic problems with muscle weakness and, occasionally, mild paralysis. Individuals are generally born with the disorder, although symptoms may not manifest until much later in life. Most cases are inherited, and it only takes one parent with the faulty gene to pass the disorder on to the child. Hypokalemic periodic paralysis is very uncommon, affecting only about one in every 100,000 individuals. Asian men with thyroid disorders generally have a higher risk-level than other groups.
People with hypokalemic periodic paralysis have a problem maintaining their potassium levels. Their bodies process potassium inappropriately in relation to muscle function, and they use it up very quickly. When the potassium levels drop too low, an episode of muscle weakness will generally occur. The length of an episode can vary quite a bit. Sometimes people will only suffer for a few hours, but symptoms can also persist for days at a time.
Hypokalemic periodic paralysis can attack several different muscle sets. The legs and arms are generally more commonly affected than other areas. Facial muscles can also be weakened, along with smaller muscles in the hands and feet. Some patients suffer problems with the muscles related to swallowing or talking and breathing, and this is particularly dangerous. Sometimes the weakness is accompanied with overall muscle soreness, but in other cases, it is generally painless. The episodes may get worse as a person ages, and over time, some of the weakness may begin to persist in-between episodes.
Diet has been implicated as the trigger that generally causes a bout of muscle weakness. Salt has been blamed in some cases, along with overindulgence in carbohydrate foods. Some episodes seem to be triggered by taking in alcoholic beverages, and some experts think people with hypokalemic periodic paralysis should avoid alcohol completely. Most outbreaks seem to occur after a person wakes up from sleeping, and they almost never happen while a person is awake and active. The exact reason for this is unknown.
The most common medical approach is to give the patient a carbonic anhydrase inhibitor drug, such as Diamox or Daranide. These drugs can help a person maintain a good potassium balance. Certain diuretics can also be used because they force the kidneys to waste less potassium. Once a patient feels symptoms of an episode beginning, he will generally take some form of potassium tablet in an effort to short-circuit the process.