WHAT IS LEMS?

Important facts about Lambert-Eaton myasthenic syndrome (LEMS)

LEMS IS a neuromuscular disorder (a condition that affects the nerves and muscles) that typically causes severe, debilitating, and progressive muscle weakness and fatigue.

LEMS OCCURS WHEN the immune system disrupts communication between the nerves and muscles in an area known as the neuromuscular junction (NMJ).

LEMS DISRUPTS the ability of nerves to release an important chemical called acetylcholine (ACh). When ACh is not released properly, muscles lose the signal necessary for their full function. As a result, people with LEMS may struggle to walk or do everyday activities.

Illustration of the signal breakdown between nerves and muscles

WHO IS AFFECTED BY LEMS? 

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Approximately 3,000 people in the US

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First symptoms usually appear between ages 35 and 60

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Both men and women are affected

SYMPTOMS OF LEMS include muscle weakness, especially in the legs and hips. This weakness may fluctuate from day to day. LEMS can make it very difficult to do everyday activities, such as walking, talking, or lifting objects. Some patients may have to use assistive equipment, such as a wheelchair or walker, to get around. If you suspect that you may have LEMS, talk to your doctor about the symptoms you’re experiencing and your possible treatment options.

Could your symptoms be a sign of LEMS?

TAKE A SHORT SELF-ASSESSMENT AND TALK TO YOUR DOCTOR TO SEE WHAT YOUR SYMPTOMS MAY BE TRYING TO TELL YOU

We’ll send you a summary of your responses, along with other helpful information that you can use when talking with your physician.

Take the Assessment
LEMS human Icon

THANK YOU FOR YOUR TIME!

Watch your inbox for your symptom assessment summary.

LEMS IS COMMONLY MISDIAGNOSED because its symptoms resemble other more common diseases, including:

  • Myasthenia gravis (MG)
  • Multiple sclerosis (MS)
  • Myopathies
  • Fibromyalgia
  • Amyotrophic lateral sclerosis (ALS)
  • Depression

Many people with LEMS struggle with symptoms for years before finally getting diagnosed. For that reason, it’s important to see a physician who has experience with diagnosing neuromuscular diseases.

Who treats LEMS?

If you think that you may be experiencing symptoms of LEMS, talk to your physician. If your physician suspects that you may have LEMS, he or she may refer you to a neurologist or neuromuscular specialist. These types of doctors specialize in neuromuscular diseases like LEMS. Find a LEMS physician nearest to you now.

Mary Ann Talking

MARY ANN, A PATIENT WITH LEMS, TALKS ABOUT HER JOURNEY TO DIAGNOSIS.

Diagnostic tests your doctor may use

LEMS is typically diagnosed through one or more of the following ways:

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A physical exam to test for symptoms and reflexes

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Bloodwork to test for certain antibodies

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An electrodiagnostic test to measure how well your muscles and nerves are communicating with each other

Benefits of earlier diagnosis

An early, accurate diagnosis can benefit LEMS patients in several ways:

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Feeling better sooner – The earlier you know what’s causing your symptoms, the sooner they can be treated.

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Maintaining strength – Studies show that effective treatment can help you maintain your strength to support muscle function and mobility.

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Uncovering hidden disease – If you are diagnosed with LEMS, you may be at increased risk for certain types of cancer.

MORE ABOUT LEMS AND CANCER 

For some patients, their LEMS symptoms are an important early warning sign that may help save their lives.

Graphic illustrating the ratio of 5 of 10 patients

About 50% of people with LEMS have an underlying cancer—often small cell lung cancer

The majority of these cases occur in patients with a history of smoking

Your treating physician may recommend cancer screenings when you are diagnosed with LEMS and periodically thereafter.

FIRDAPSE Education Brochure

Educational Brochure

Download an educational brochure about LEMS and how FIRDAPSE may help.
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What is FIRDAPSE®?

FIRDAPSE is a prescription medicine used to treat adults 17 years of age or older with Lambert-Eaton myasthenic syndrome (LEMS). The safety and efficacy of FIRDAPSE in patients under the age of 17 has not been established.

IMPORTANT SAFETY INFORMATION

What is the most important information I should know about FIRDAPSE?

  • FIRDAPSE can cause seizures.
    • You could have a seizure even if you never had a seizure before.
    • Do not take FIRDAPSE if you have ever had a seizure.

Stop taking FIRDAPSE and call your doctor right away if you have a seizure while taking FIRDAPSE.

Do not take FIRDAPSE if you:

  • have ever had a seizure.
  • are allergic to amifampridine phosphate, or another aminopyridine.

Before you take FIRDAPSE, tell your doctor about all of your medical conditions, including if you:

  • are taking another aminopyridine, such as compounded 3,4-diaminopyridine (3,4-DAP)
  • have had a seizure
  • have kidney problems
  • have liver problems
  • are pregnant or plan to become pregnant. It is not known if FIRDAPSE will harm your unborn baby. You and your doctor will decide if you should take FIRDAPSE while you are pregnant.
  • are breastfeeding or plan to breastfeed. It is not known if FIRDAPSE passes into your breast milk. Talk to your doctor about the best way to feed your baby while taking FIRDAPSE.

Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

How should I take FIRDAPSE?

  • Take FIRDAPSE exactly as your doctor tells you to take it. Do not change your dose of FIRDAPSE.
  • Do not take more than 2 tablets of FIRDAPSE at one time or more than 8 tablets of FIRDAPSE in a 24-hour period.
  • FIRDAPSE can be taken with or without food.
  • If you miss a dose of FIRDAPSE, skip that dose and take your next dose at your next scheduled dose time. Do not double your dose to make up the missed dose.
  • Do not take FIRDAPSE together with other medicines known to increase the risk of seizures.
  • If you take too much FIRDAPSE, call your doctor or go to the nearest hospital emergency room right away.

What are the possible side effects of FIRDAPSE?

FIRDAPSE may cause serious side effects, including:

  • Seizures. See "What is the most important information I should know about FIRDAPSE?"
  • Serious allergic reactions, such as anaphylaxis. FIRDAPSE can cause serious allergic reactions. Stop taking FIRDAPSE and call your doctor right away or get emergency medical help if you have:
    • shortness of breath or trouble breathing
    • swelling of your throat or tongue
    • ­hives
  • The most common side effects of FIRDAPSE include:
    • tingling around the mouth, tongue, face, fingers, toes, and other body parts
    • upper respiratory infection
    • stomach pain
    • nausea
    • diarrhea
    • headache
    • increased liver enzymes
    • back pain
    • high blood pressure
    • muscle spasms

Tell your doctor if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of FIRDAPSE.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

How should I store FIRDAPSE?

  • Store FIRDAPSE at 68ºF to 77ºF (20ºC to 25ºC).
  • Safely throw away FIRDAPSE that is out of date or no longer needed.

Keep FIRDAPSE and all medicines out of the reach of children.

If you would like more information, ask your doctor or pharmacist for additional information about FIRDAPSE.

The active ingredient in FIRDAPSE is amifampridine phosphate. Inactive ingredients are calcium stearate, colloidal silicon dioxide, and microcrystalline cellulose.

Please see full Prescribing Information for additional Important Safety Information.

What is FIRDAPSE®?

FIRDAPSE is a prescription medicine used to treat adults 17 years of age or older with Lambert-Eaton myasthenic syndrome (LEMS). The safety and efficacy of FIRDAPSE in patients under the age of 17 has not been established.

IMPORTANT SAFETY INFORMATION

What is the most important information I should know about FIRDAPSE?

  • FIRDAPSE can cause seizures.
    • You could have a seizure even if you never had a seizure before.
    • Do not take FIRDAPSE if you have ever had a seizure.

Stop taking FIRDAPSE and call your doctor right away if you have a seizure while taking FIRDAPSE.

Do not take FIRDAPSE if you:

  • have ever had a seizure.
  • are allergic to amifampridine phosphate, or another aminopyridine.

Before you take FIRDAPSE, tell your doctor about all of your medical conditions, including if you:

  • are taking another aminopyridine, such as compounded 3,4-diaminopyridine (3,4-DAP)
  • have had a seizure
  • have kidney problems
  • have liver problems
  • are pregnant or plan to become pregnant. It is not known if FIRDAPSE will harm your unborn baby. You and your doctor will decide if you should take FIRDAPSE while you are pregnant.
  • are breastfeeding or plan to breastfeed. It is not known if FIRDAPSE passes into your breast milk. Talk to your doctor about the best way to feed your baby while taking FIRDAPSE.

Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

How should I take FIRDAPSE?

  • Take FIRDAPSE exactly as your doctor tells you to take it. Do not change your dose of FIRDAPSE.
  • Do not take more than 2 tablets of FIRDAPSE at one time or more than 8 tablets of FIRDAPSE in a 24-hour period.
  • FIRDAPSE can be taken with or without food.
  • If you miss a dose of FIRDAPSE, skip that dose and take your next dose at your next scheduled dose time. Do not double your dose to make up the missed dose.
  • Do not take FIRDAPSE together with other medicines known to increase the risk of seizures.
  • If you take too much FIRDAPSE, call your doctor or go to the nearest hospital emergency room right away.

What are the possible side effects of FIRDAPSE?

FIRDAPSE may cause serious side effects, including:

  • Seizures. See "What is the most important information I should know about FIRDAPSE?"
  • Serious allergic reactions, such as anaphylaxis. FIRDAPSE can cause serious allergic reactions. Stop taking FIRDAPSE and call your doctor right away or get emergency medical help if you have:
    • shortness of breath or trouble breathing
    • swelling of your throat or tongue
    • ­hives
  • The most common side effects of FIRDAPSE include:
    • tingling around the mouth, tongue, face, fingers, toes, and other body parts
    • upper respiratory infection
    • stomach pain
    • nausea
    • diarrhea
    • headache
    • increased liver enzymes
    • back pain
    • high blood pressure
    • muscle spasms

Tell your doctor if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of FIRDAPSE.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

How should I store FIRDAPSE?

  • Store FIRDAPSE at 68ºF to 77ºF (20ºC to 25ºC).
  • Safely throw away FIRDAPSE that is out of date or no longer needed.

Keep FIRDAPSE and all medicines out of the reach of children.

If you would like more information, ask your doctor or pharmacist for additional information about FIRDAPSE.

The active ingredient in FIRDAPSE is amifampridine phosphate. Inactive ingredients are calcium stearate, colloidal silicon dioxide, and microcrystalline cellulose.

Please see full Prescribing Information for additional Important Safety Information.