Christina Applegate's MS Misdiagnosis Highlights Common Issue in Medical Field
Updated 17:48 20 Oct 2026 GMT+1Published 16:32 20 Oct 2026 GMT+1
New technology led to the discovery and now Christina Applegate's illness is a mystery
Earlier today (20 October), Christina Applegate she has been misdiagnosed with multiple sclerosis (MS). The actor was diagnosed with the condition back in 2021 and has been living with debilitating symptoms.
Applegate said she’s now ‘back at square one’ as she doesn’t know what’s wrong with her. And unfortunately, this is a shared experience.
Joining the Anchorman actor on her podcast MeSy with Jamie-Lynn Sigler, a doctor explained MS misdiagnoses are ‘fairly common’.
Associate professor with the Cedars-Sinai Medical Center department of neurology, Dr Marwa Kaisey explained that nearly 20 percent of people diagnosed with the condition turn out not to have it.
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“Almost one in five of these people who’d been told they had MS, some for decades, didn’t actually have it,” she explained. “And a majority of them were on medication to treat their MS.”
Christina Applegate is 'not happy at all' about the news of her misdiagnosis (Axelle/Bauer-Griffin/FilmMagic)
Dr Kaisey told Applegate and Sigler that there isn’t ‘one single test’ for the condition.
“It’s not like we have something like a pregnancy test that says, ‘Yes. You have it.’ ‘No. You don’t.’ It’s a list of criteria,” she said.
Applegate echoed this as she said she has ‘every single’ symptom of ‘someone with MS’ but ‘something else is going on’.
A report shared in the National Library of Medicine, titled Multiple Sclerosis Misdiagnosis: A Persistent Problem to Solve, explores this.
Applegate says she's 'back at square one' (Instagram/@christinaapplegate)
It lays out that ‘no specific disease biomarker exists’ which means the ‘diagnosis is not always a straightforward process’.
“MS has heterogeneous clinical and imaging manifestations, which not only differ between patients, but also vary in individual patients over time. Disease signs and symptoms, presence of oligoclonal bands (OCB) and MRI findings have limited specificity, and misdiagnosis remains a problem with significant clinical and psychosocial implications for both patients as well as health care providers."
"Although the problem of MS misdiagnosis is known, true incidence and prevalence is not."
(LADbible)
It also adds that a wide range of conditions can be mistaken for MS including: “Migraine, cerebral small vessel disease, fibromyalgia, functional neurological disorders, and neuromyelitis optica spectrum disorders, along with uncommon inflammatory, infectious and metabolic conditions.”
And as Applegate says, a misdiagnosis does not mean being better – her symptoms remain and her illness is now a mystery.
“It’s clear now that they’re finding something different,” Applegate continued. “Something else is going on.”
Her illness is now a mystery (Leon Bennett/Getty Images)
During the emotional episode of her podcast, she said that new technology led to the discovery around her health.
“This may come as great news, but to me, I’m back at square one,” Applegate said. “It’s hard to say that [my doctor] came into my room and she said, 'Congratulations, you don’t have MS'.”
The star is ‘not happy at all’ about the news, as it’s not like she’s suddenly ‘gotten better’.
“If anything, I’ve gotten worse in some ways.”
Featured Image Credit: Matt Winkelmeyer/Getty Images for Critics Choice Association
Topics: Christina Applegate, Health, Celebrity
