Intended for US residents only.

Learn about LEMS from other patients by watching a LEMS Patient Webinar.

Intended for US residents only.

The recommended first-line therapy for patients living with Lambert-Eaton myasthenic syndrome (LEMS)

Clinically proven to maintain muscle strength and mobility

The FIRDAPSE Pregnancy Registry: In conjunction with the FDA, Catalyst Pharmaceuticals has created a registry to collect information about the safety of FIRDAPSE use in the event of pregnancy. Patients with LEMS—even those not taking FIRDAPSE—may enroll. Contact the registry as soon as you learn that you are pregnant by calling 1-855-212-5856 or visiting

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Use the Physician Locator to find the LEMS physicians closest to your area.

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Catalyst Pathways® offers a range of free, personalized support and financial services for FIRDAPSE patients.

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Get Enrollment Help

Check out the Getting Started video for step-by-step assistance in completing the Catalyst Pathways Enrollment Form.