Transcript for Actress Selma Blair reveals MS diagnosis on Instagram

now to our "Gma" cover story. Actress Selma Blair revealing her health battle in a personal post opening up about the day-to-day struggles she is facing and how she is working through them. Erielle reshef is here, and we know she hopes her news will help others. Reporter: She does, robin, and in that post, she says she is a forthcoming person and she hopes this news will help others and herself as she copes with her new diagnosis and the symptoms she has been experiencing for years. She is the actress who famously played quirky roles in box office hits like "Legally blonde." You're famous in our club. Reporter: And "Cruel intentions." I am? Reporter: Now in a lengthy and candid Instagram post, Selma Blair is revealing she was recently diagnosed with multiple sclerosis, saying the doctors broke the news to her back in August writing, I am disabled. I fall sometimes. I drop things. My memory is foggy, and my left side is asking directions from a broken gps, but we are doing it. The 46-year-old mom opening up about her struggles, saying her symptoms have been around for decades. I have had symptoms for years, but was never taken seriously. I have probably had this incurable disease for 15 years, at least. It's very often that the actual sort of beginning of Ms precedes the medical diagnosis of Ms by years. Reporter: It's a degenerative disease that affects the central nervous system. About a million people are diagnosed with Ms nationwide, and even though it's incurable, many are able to live with the disease for years. Compared to 20 years ago, the treatment landscapes changed dramatically. There are many options. A person living with Ms should be able to find a disease-modifying treatment that works for them by working closely with their neurologist. Reporter: Celebrities like Jamie Lynn Sigler and jack Osbourne both living with Ms. Blair thanking her friends, and fans for the outpouring of support adding, I want my life to be full somehow. I want to play with my son again. I want to walk down the street and ride my horse. I have Ms and I am okay. May we all know good days amongst the challenges. It's a good thing to remember. Experts say Blair's case is a good example that you should trust your intuition if you feel something isn't right and you should never be afraid, robin, to seek a second opinion. She said she is feeling the love since he posted this, from famous friends, fans and of course, Netflix has also weighed in. Her boss saying he love and support her as well. She wanted to share the story because for 15 years. You know if something is not right. Exactly, and now since this post, they have had so many people posting their own personal stories and saying the signs they missed as well. Okay. Well, thank you so much, and we wish her all the best. As you said, the big days and the challenging ones as we. Yes, indeed.

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