Actress Christina Applegate has revealed that she has been diagnosed with multiple sclerosis.

The "Dead to Me" actress announced the diagnosis on Monday in a tweet, saying she was diagnosed "a few months ago" and that "it's been a tough road."

"It’s been a strange journey. But I have been so supported by people that I know who also have this condition. It’s been a tough road. But as we all know, the road keeps going," the "Married... with Children" actress tweeted.

In a later tweet, the Emmy-winning actress added that she now asks for privacy, and she goes "through this thing."

According to the Mayo Clinic, multiple sclerosis, also known as MS, is an autoimmune disease that attacks the central nervous system, and there is no known cure.

According to the National Multiple Sclerosis Society, MS affects more than 2.3 million people worldwide.