Eric Dane just revealed in April that he’d been diagnosed with amyotrophic lateral sclerosis (ALS), but he’s already lost function in his right arm and worries about weakness on his left side and in his legs.

“My left side is functioning, my right side has completely stopped working,” the Grey’s Anatomy alum said, after sharing he only had “one functioning arm,” in an interview with Diane Sawyer that aired on Monday and Tuesday’s Good Morning America. “I feel like maybe a couple more months and I won’t have my left hand either. It’s sobering.”

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Dane, who appeared somewhat physically weak in the pre-taped conversation, already had a scary incident with his 13-year-old daughter when the former competitive swimmer and water polo player jumped into the water and realized he didn’t have the strength to swim.

“She dragged me back to the boat,” he said of his child, adding that he broke down in tears. “I was just, I was, like, heartbroken.”

Dane said his symptoms began over a year ago when he started to notice weakness in his right hand.

“I didn’t really think anything of it at the time. I thought maybe I’d been texting too much or my hand was fatigued,” he recalled. “But a few weeks later, I noticed it had gotten a little worse.”

He then ended up seeing a series of doctors, including two hand specialists and neurologists, the second of which told him, “This is way above my pay grade.”

After nine months of testing, he got the ALS diagnosis: “I’ll never forget those three letters.”

The neurological disorder, also known as Lou Gehrig’s disease, affects motor neurons, a type of nerve cell in the brain and spinal cord that control voluntary muscle movement and breathing, according to the National Institutes of Health. As these cells deteriorate, muscles weaken and waste away and the brain loses its ability to start and control functions like walking, talking, chewing and breathing. The disease gets worse over time.

Dane, who plays Cal Jacobs on Euphoria and stars in the upcoming Prime Video police thriller Countdown, was focused on his family as he talked to Sawyer and said he wants to work as long as he’s able.

“I mean, I really, at the end of the day, just, all I want to do is spend time with my family and work a little bit if I can,” he said. “I don’t think this is the end of my story. I just don’t feel like, in my heart, I don’t feel like this is the end of me.”

He grew emotional when he referenced wife, Rebecca Gayheart, whom he called his “biggest champion.”

“I talk to her every day,” he said, pausing to collect himself as he got choked up. “We have managed to become better friends and better parents. And she is … probably my biggest champion and my most stalwart supporter. And I lean on her.”

And after losing his own father to suicide at the age of 7, Dane is “angry” the disease could also take him from his teenage daughters while they’re young.

“I’m angry because, you know, my father was taken from me when I was young,” he said. “And now, you know, there’s a very good chance I’m going to be taken from my girls while they’re very young.”

There’s currently no known cure for ALS, and most people die from being unable to breathe on their own, usually within three to five years of symptoms first appearing, according to NIH. Approximately 10 percent of people diagnosed with ALS survive for 10 years or more.

Sawyer had teased the second part of the interview, which aired on Tuesday, when she would speak with Dane and his doctor, Dr. Merit Cudkowicz, the executive director at Massachusetts General Brigham Neuroscience Institute.

“It’s a hard diagnosis to hear, but I want them to hear that there’s hope,” said Cudkowiczm, speaking to others with ALS, which she said affects 5,000 people per year and is a number that is rising too quickly. “I never want anyone to hear that there’s nothing to do because there’s a lot to do.”

Cudkowiczm said it’s predicted by 2040 that the numbers of people with ALS worldwide will increase at least 40 percent, due to the aging population and environmental factors including plastics, bacteria in lakes, pesticides, being in the military and head trauma. She also spoke about a new breakthrough drug that has been showing improvements in clinical testing.

Dane, who doesn’t qualify for that trial per gene testing, is taking medication to slow down the symptoms and participating in a different research study. “I will fly to Germany and eat the head off a rattlesnake if she told me that will help,” said Dane, with a smile, of being open to trying anything to combat the disease.

The Ice Bucket Challenge that went viral starting in 2014 has raised $200 million for U.S. research.

“I’m pretty hopeful,” closed Dane. “In my heart, I don’t feel like this is the end of me.”

— Jackie Strause contributed to this story.

This story first posted on June 16 at 5:58 am PT and was updated on June 17 at 6:30 a.m. with Dane’s Tuesday interview on GMA.

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