Kristen Johnston Kristen Johnston

After going public with her diagnosis in December, Kristen Johnson is opening up about her ongoing struggle with lupus.

"I went to 17 doctors, and nobody could figure out what was going on," the 3rd Rock from the Sun star tells People. "I didn't know what was going to happen to me." 

After starting to feel sick in September, Johnston was diagnosed a few months later with lupus myelitis, a rare form of the disease that affects the spinal cord. By that time, the autoimmune disease had already progressed to the point where Johnston was so weak and exhausted that she couldn't lift her neck without a brace. "If I had to live like that forever, I would have killed myself," she said.

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Johnston, 46, checked into a hospital and began chemotherapy and steroid treatment. "She's in remission," her doctor, Daniel J. Wallace, confirms. "But if she'd waited a few weeks longer, she could have ended up quadriplegic."

The two-time Emmy winner remains positive about her recovery. "Every day I'm amazed that I can lift my head," she says. "Every single day is a gift, and I don't take one second of it for granted."

Johnston currently stars on The Exes, which was renewed for a fourth season earlier this year.

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