Periodic Paralysis (PP)
What is periodic paralysis?
Periodic paralysis (PP) is a rare genetic disorder that is characterized by sudden attacks of paralysis, weakness, and stiffness. There are a number of different forms of PP, and the major ones are hyperkalemic PP, hypokalemic PP, Andersen-Tawil syndrome, and thyrotoxic PP.
What are the symptoms of periodic paralysis?
Some people begin experiencing the symptoms of PP in childhood, while others do not see the effects until they are adults. Severity ranges as well; some people have attacks frequently while others do not. The specific symptoms depend on which form of PP one has, but there are a number of common effects:
- Muscle cramps
- Attacks of muscle weakness that can last anywhere from minutes to days
- Permanent weakness
- Muscle pain after exercise
What causes periodic paralysis?
Each form of PP has its own genetic cause, but every type is the result of issues with ion channels. These issues make it so that the muscle cells do not respond to nerve cells; they do not expand or contract.
The majority of genetic mutations that cause periodic paralysis are inherited in an autosomal dominant pattern, but a number of them aren’t and even more have yet to be discovered.
How is periodic paralysis diagnosed?
Doctors will begin by looking for the characteristic symptoms, asking about family and medical history, and performing a physical exam. Tests will follow, such as blood tests, genetic tests, electrocardiograms, electromyographies, and nerve conduction studies.
What are the treatments for periodic paralysis?
The goal of treatment is to lower the number and severity of attacks. Doctors do so through controlling potassium and carbohydrate intake through supplements and a specific diet, prescribing dichlorphenamide, limiting exposure to triggers, exercising in moderation, controlling thyroid function, prescribing acetazolamide, carbonic anhydrase inhibitors, heart medications or potassium-sparing diuretics.