Christina Applegate says she’s “back at square one” after more than five years of believing she had multiple sclerosis (MS) — only for a doctor to tell her she doesn’t.
“‘Congratulations. You don’t have MS,’ ” the “Dead to Me” actress, 54, recalled her doctor saying. Yet she was “not happy at all” about the revelation.
“I’m back at square one, that I don’t know what’s going on with me,” she said Tuesday on her podcast, “MeSsy,” which she hosts with fellow actor Jamie-Lynn Sigler, who was diagnosed with MS in 2001.
MS causes the immune system to attack the protective covering on nerve fibers, disrupting communication between the brain and the rest of the body. That disruption may become permanent, and patients can lose the ability to walk on their own or move at all.
Misdiagnosis affects more people than you might think.
“Up to 1 in 5 patients diagnosed with MS may not actually have MS but a different condition,” Dr. Elena Grebenciucova, an MS and neuroimmunology physician at Northwestern Medicine, told The Post. “Symptoms of MS are not unique to MS.”
A misdiagnosis doesn’t just confuse and distress patients. Shortly after being diagnosed with MS, patients often start therapies that suppress the immune system to slow long-term disability progression.
Improper treatment can cause severe injury and unnecessary health risks.
“You don’t get misdiagnosed and then all of a sudden I’m better,” Applegate said. “I haven’t gotten better, Jamie. If anything, I’ve gotten worse in some ways.”
Here’s how an MS misdiagnosis can occur — and the next steps Applegate is taking to identify the correct cause of her health woes.
What are Applegate’s symptoms?
Applegate reported first experiencing a tingling sensation in her toes in early 2021 that gradually led to “insane tingling” from her “butt down.”
She also felt her leg buckling while shooting scenes for Netflix’s “Dead to Me.”
She required a wheelchair during the 2021 filming and has walked with a cane since.
“My knees feel like I have bricks attached to them, heavy and painful,” Applegate noted as she reflected on her symptoms. “When I put my feet down on the ground when I wake up, it feels as if the floor is made of needles, yet I can’t feel them because my feet are completely numb.”
She detailed other struggles in her 2026 memoir, “You With the Sad Eyes.”
“When I wake up, I often can’t get my arm to move far enough to grab the cup of water by my bed or my phone from its charger,” she wrote.
“My stomach frequently slows to a halt, leaving me to regularly rush to the emergency room in agony.”
What are the symptoms of MS?
MS, which is believed to affect nearly 1 million Americans, might start with vision problems (such as double vision, pain with eye movement or vision loss), muscle weakness (often in the arms and legs), muscle stiffness and muscle spasms. This can lead to clumsiness and difficulty balancing.
It could also manifest as tingling, numbness or pain in the limbs, abdomen or face; loss of bladder control; and/or dizziness. There can also be cognitive and emotional changes: problems concentrating and difficulty with emotional expression and control.
Over time, muscle weakness and pain can affect walking or standing or lead to paralysis.
About 20% to 40% of MS cases progress steadily, with some periods when the disease doesn’t get worse.
Most people have relapse-remitting MS, where new symptoms or “relapses” emerge over days or weeks, then improve or disappear completely.
What steps is Applegate taking to get the proper diagnosis?
Anyone who believes they might have been misdiagnosed with MS should visit an MS specialist.
“It’s important to talk to a neuro-immunologist at an academic center to review whether this is autoimmune and what other mimics of MS may have not been investigated,” Grebenciucova said.
Applegate said on her Tuesday podcast episode that her doctors are embarking on “an online investigation … to find out what has been going on since 2021, why did this happen?”
Dr. Marwa Kaisey, an associate professor of neurology at Cedars-Sinai in LA, said on the podcast that it’s imperative to find the cause of Applegate’s inflammation.
“The next steps are to try to get them an answer as to what’s actually going on, and that looks different in each patient,” Kaisey explained.
“For someone like Christina, who has these bands in her spinal fluid [the diagnostic hallmark that was the basis for her MS diagnosis], there’s probably something causing inflammation within her central nervous system, so that’s the road that you might go down and look for things that might be inflammatory causes.”
Rheumatoid arthritis, a chronic autoimmune condition, is being explored, Applegate said on the podcast. Her rep had no further comment to The Post.
Which conditions are often mistaken for MS?
Many diseases manifest symptoms similar to MS, which are called “MS mimics.”
“For example, tingling or blurry vision can occur due to dozens of other diagnoses. Imbalance, likewise, can occur due to a variety of conditions,” Grebenciucova said.
Because there is no single test that can identify MS, sometimes the only way to identify it is to rule out other possibilities.
This includes autoimmune disorders like acute disseminated encephalomyelitis (ADEM), systemic lupus erythematosus (SLE), Sjögren’s syndrome, myasthenia gravis (MG) and sarcoidosis.
Lyme disease, human T-cell lymphotropic virus-1 (HTLV-1) and syphilis that spreads to the brain are a few infectious diseases that can look like MS. Stroke, ALS, muscular dystrophy, hypothyroidism, hypertension and many other mimics add to the chaos.
To make matters even more complicated, MS looks very different between people and can even vary in the same person over time.
Because starting medication for MS early makes such a big difference — if the patient actually has it — pressure to quickly establish a diagnosis could also increase misdiagnoses.
What are red flags of misdiagnosis?
When patients show features outside a typical MS case (called “red flags”), a new diagnosis isn’t always made.
Experts say this may be because many MS doctors often encounter unusual MS cases and consider them a part of the spectrum of the disease.
Plus, when patients transfer or get referred to a new doctor, that provider may just accept the previous diagnosis without question. Also, doctors are human too: they may not want to admit they’re wrong.
According to the National MS Society, bilateral vision loss, seizures, headache, abrupt onset of symptoms and hiccups lasting more than a month are some of the red flags that could indicate an MS diagnosis is actually something else.