Actress Christina Applegate Discovers Her Multiple Sclerosis Diagnosis Was Wrong, But Symptoms Persist

Key points

• Applegate announced the misdiagnosis on her podcast 'MeSsy' on October 20, 2026, more than five years after her initial 2021 diagnosis.
• Her doctor discovered the error while investigating her B-cell response after stopping an infusion treatment.
• Applegate's debilitating symptoms, including mobility issues and the need for a wheelchair, persist and have potentially worsened.
• Doctors are now investigating the true cause of her condition, which remains unexplained.
• Applegate expressed feeling confused and like she had 'let everybody down' after becoming an MS advocate.

Background

Applegate first disclosed her MS diagnosis in 2021 and became an outspoken advocate for the condition. She previously described using a wheelchair during filming of 'Dead To Me' and struggling to parent her 15-year-old daughter due to her health limitations. In September 2026, she returned to social media after a four-month hospital stay, confirming she was home and recovering.

How outlets are covering it

All outlets report the core facts of the misdiagnosis and persistent symptoms. CBS News and Fox News emphasize Applegate's emotional reaction, describing her as 'not happy' and feeling she had 'let everybody down.' Fox News highlights her statement that she is 'back at square one' and her confusion about the cause of her symptoms. AP News provides a more concise summary, focusing on the medical investigation into her condition. Dr. Marwa Kaisey, a neurologist, noted on the podcast that MS misdiagnoses are 'fairly common,' with almost one in five people told they have MS not actually having it.

Why it matters

This case highlights the challenges of diagnosing multiple sclerosis, which lacks a single definitive test. It also underscores the emotional and practical impact of a misdiagnosis on a public figure who had built her advocacy around the condition. The ongoing mystery of Applegate's symptoms raises questions about the accuracy of neurological diagnoses and the need for thorough medical investigations.

What to watch

Applegate's doctors are set to begin an investigation next week to determine the true cause of her symptoms and why she was initially misdiagnosed with MS. She will continue to share updates on her health journey through her podcast 'MeSsy.'