This may be partly because there are over 130 currently known different mutations that can cause the disorder, each with their own specifics, and also because myotonia congenita is an ion channel disorder, and ion channels are sensitive to internal and external environmental factors. It has been shown that pregnancy and the use of diuretics aggravate myotonia, and both these conditions are linked to the loss of divalent cations such as magnesium and calcium. It has further been shown that in chemically-induced myotonia in isolated rat muscle, myotonia could be dampened by increasing the magnesium and calcium content of the extracellular medium. This has also been shown for isolated human muscle.Adrenaline/epinephrine is well known to make myotonia worse in most individuals with the disorder, and a person with myotonia congenita may experience a sudden increase in difficulty with mobility in a particularly stressful situation during which adrenaline is released.Due to the invisible nature of the disorder, the fact that those with myotonia congenita often appear very fit and able bodied, the general lack of knowledge about the disorder by the general and medical community, and often by the individual themselves, and the potential for inconsistency with the symptoms, many people with myotonia congenita have experienced a degree of social persecution at one time or another because of the effects of their disorder.
Sycosis vulgaris  is a cutaneous condition characterized by a chronic infection of the chin or bearded region. : 252  The irritation is caused by a deep infection of hair follicles, often by species of Staphylococcus or Propionibacterium bacteria. Asymptomatic or painful and tender erythematous papules and pustules may form around coarse hair in the beard (sycosis barbae) or the back of the neck  (sycosis nuchae). See also
Folliculitis
List of cutaneous conditions


== References ==