"In addition to all the other things that can make you feel tired or sleepy, you can add to the list another type of fatigue, commonly referred to as LASSITUDE, that's unique to people with MS. Lassitude is thought to result from poor nerve conduction caused by damage to the myelin around the nerve fibers in the central nervous system (CNS). Because of the demyelination, your body has to work harder just to transmit messages between your brain and other parts ofyour body. Unlike normal fatigue, MS lassitude:
- tends to come on suddenly
- generally occurs on a daily basis
- can occur at any time of day, even in the morning after a restful night's sleep
- generally increases as the day progresses
- can worsen temporarily with heat and humidity
- is much more likely to interfere with everyday activities"