Michel,

It's a lot easier and less painful to do a DNA test for the various myotonias. Most Canadian doctors order the myotonic profile from Athena Diagnostics in Massachusetts. That covers both chloride and sodium channel myotonias as well as myotonic muscular dystrophy.

The chloride channel myotonias (Thomsen's and Becker's) tend to stay the same as you age, but paramyotonia congenita and myotonic MD usually are progressive. Myotonic dystrophy is often diagnosed by an optometrist because of a very unique type of cataract that forms in the 20s or 30s. Paramyotonia congenita can give mixed results on an EMG. Sometimes it doesn't show up at all unless they chill the muscles being tested.

What you're describing sounds a bit more like Stiff Person Syndrome or neuromyotonia. Have you ever read about those conditions? All of these variations that involve myotonia have different treatments so you really have to have a definitive diagnosis to know which is best. In general Mexitil (mexiletine) seems to work best for the myotonias but there are also medications like Diamox, Dilantin and even Quinine Sulfate that work for many people.

Until you have more testing you might want to try taking 500 mg of Acetyl-L-Carnitine and see if that helps with your exercise tolerance. Magnesium is also very helpful for spasms and cramping. Usually 250 to 500 mg per day is adequate. Those two supplements should help improve many different muscle conditions.

Jan

Type of Myotonia: Thomsen's

Country: USA