LEMS To Light 

LEMS Aware was created to help physicians recognize, diagnose, and treat Lambert-Eaton myasthenic syndrome (LEMS), a rare, yet frequently unrecognized, neuromuscular disorder.1


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Information to help you change lives.

LEMS Aware delivers relevant content, resources, and expert insights to assist physicians who may encounter, or be treating, patients with LEMS. Wherever your patient is on their journey to feeling better—searching for a diagnosis or the right treatment—this site can help you guide them to that next milestone.

On the basis of our experience with the six patients, three of whom were found to have intrathoracic malignant lesions…it is interesting to speculate that the neuromuscular syndrome described may in some way be related to the malignancy.

Should this syndrome prove to be of some clinical importance, electromyography and stimulation of nerves must be given the greatest credit. Without these techniques, the syndrome would have been confused with myasthenia gravis and its significance would have continued to elude us.
—Eaton and Lambert, 19572
Lab scientists

What is LEMS?

Lambert-Eaton myasthenic syndrome, also known as LEMS, is an autoimmune disorder that affects neuromuscular transmission. It is named for Dr. Edward Lambert and Dr. Lee Eaton—the two Mayo Clinic neurologists who first described the clinical and electrophysiological characteristics of the syndrome in 1957.3

LEMS typically begins with lower-limb muscle weakness and general fatigue, making it difficult for patients to rise from a seated position, climb stairs, or even walk.3 LEMS can also start within or progress to the muscles of the upper arms and shoulders4, making self-care and independence difficult.3 Many patients also experience autonomic symptoms, such as dry mouth and constipation.3,4 More detailed information about LEMS and its symptoms is available in the next section.

Consult with a representative

Whether you’re familiar with LEMS or just learning about it, LEMS Aware has representatives available to answer any questions you may have.

Insights from a LEMS expert

Mazen Dimachkie, MD, FAAN, FANA, a Professor
of Neurology at The University of Kansas Medical
Center, discusses one often-misdiagnosed cause of
weakness and fatigue: LEMS.
Within this video presentation, Dr. Dimachkie walks
through determining the cause of a patient’s muscle
weakness, common clinical symptoms, and
diagnostic testing in order to help clinicians diagnose
LEMS. Excerpts from this presentation appear
throughout this website, and you can watch the full
webinar here

LEMS And Pregnancy

LEMS Pregnancy Registry: In conjunction with the FDA, Catalyst Pharmaceuticals has created a registry to collect information about patients receiving treatment for LEMS during pregnancy.

Learn more about this registry here.

LEMS and

In 2020, the COVID-19 Working Group—an international coalition of physicians and scientists—released treatment guidelines for patients with LEMS and related neuromuscular conditions during the coronavirus pandemic.5 Since that article was published, the situation has evolved significantly.

The American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) continues to review the currently available resources and recommendations published by the most reputable sources of healthcare information to put together guidance for physicians treating patients with neuromuscular disorders.

Visit the AANEM website to find the latest guidance regarding COVID-19.


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LEMS differential diagnosis

There are several neuromuscular conditions that share clinical symptoms with LEMS and can lead to delays in diagnosis and appropriate treatment.1,4 Discover key clues that can help expedite a diagnosis for your patients.


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Tips for telehealth diagnosis

With the rise of the COVID-19 pandemic, the convenience and safety of telemedicine continue to make sense for patients dealing with mobility issues and increased health risks associated with a suspected neuromuscular condition. Find helpful tips for making a remote diagnosis of LEMS.


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The link between LEMS and cancer

Learn more about the connection between cancer and LEMS and how a LEMS diagnosis may help uncover a hidden malignancy.