LEMS and Fatigue

Fatigue is a common symptom of Lambert-Eaton myasthenic syndrome (LEMS). Feeling tired even after getting enough sleep, or becoming excessively tired or experiencing muscle weakness after exertion (especially in the upper arms and shoulders) are signs of fatigue.

How nerve signals are transmitted

Nerve cells carry messages to and from the brain to the muscles in the form of electrical signals. These electrical signals are transmitted to the muscles at the neuromuscular junction, where neurotransmitters or cell signaling molecules are released from the nerve cell ending and bind to receptors found on muscles to signal them to move.

What causes fatigue in LEMS?

In LEMS, the immune system mistakenly attacks nerve cell endings and causes damage. The damaged nerve cell endings cannot transmit nerve signals to the muscles. Without consistent nerve signals from the brain, muscles weaken and atrophy over time.

For patients, this means that normal activities such as walking, getting dressed, and doing household chores can be more tiring than they should be.

Stress, lack of sleep, and heat can all contribute to fatigue.

Treatment of fatigue in LEMS

Treatments for LEMS, which increase nerve signals and strengthen muscle response to those nerve signals, may help reduce fatigue.

Regular sleep and exercise may also help. Patients with muscle weakness can work with physical therapists to develop a safe and effective exercise routine to improve strength and range of motion.

Patients can also use strategies to manage fatigue, such as limiting alcohol and caffeine intake, maintaining a sleep journal to ensure they get enough sleep, and limiting the use of electronics before bedtime.


Last updated: July 22, 2019


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