Christina Applegate announced she was misdiagnosed with multiple sclerosis after living with the condition for five years, though she continues to experience debilitating symptoms.

Actress Christina Applegate announced on Tuesday that she was misdiagnosed with multiple sclerosis, a condition she believed she had for more than five years. Applegate shared the news on her podcast, MeSsy, explaining that her doctors concluded she does not have the disease after she stopped an infusion treatment and her body did not react as expected. While the diagnosis has been cleared, Applegate stated that her health symptoms have worsened, leaving her to seek a new medical investigation.

Discovery of the Misdiagnosis

Applegate’s realization began when her doctor suggested pausing her infusion treatment to observe how her B cells reacted. When her cell count remained stable, it prompted further investigation into her diagnosis. Ultimately, her physician informed her that she did not have multiple sclerosis, a moment Applegate described as distressing rather than relieving, noting that she was not happy to receive the news while others around her were.

Medical Context on MS Misdiagnosis

Dr. Marwa Kaisey, a neurologist at Cedars-Sinai Medical Center, explained on the podcast that misdiagnoses for multiple sclerosis are common because there is no single, universal test for the disease. Instead, it is diagnosed using a list of criteria. Research suggests that approximately 15% to 20% of patients initially diagnosed with MS may not actually have the condition. Experts noted that brain lesions, which are often used to identify MS, can also be caused by other issues such as migraines, high blood pressure, or vitamin B12 deficiencies.