Christina Applegate's Daughter Sadie, 13, Reveals She Was Diagnosed with POTS: What Is It?

Christina Applegate’s daughter Sadie is opening up about some of her own health issues. 

The Dead to Me star’s 13-year-old daughter appeared as a guest on the June 25 episode of her mom's MeSsy podcast, which she hosts alongside close friend and actress Jamie-Lynn Sigler. 

During the show, Sadie revealed that she was diagnosed with postural orthostatic tachycardia syndrome (POTS), a condition that affects blood flow, causing varying symptoms when you transition from lying down to standing up, such as fatigue, dizziness and a fast heart rate. It affects about 1 to 3 million people in the United States.

"It affects my heart, and so when I stand up, I get really, really dizzy, and my legs get really weak, and I feel like I'm going to pass out," Sadie explained. "I have fainted before, and I have gone unconscious."

Although she received her diagnosis a few months ago, Sadie said she’s dealt with the condition “for a long time,” recalling visiting the nurse "multiple times a day" in the sixth grade because she often felt like she was going to pass out.

But the school, she said, attributed her symptoms to anxiety. "They wouldn't do anything for it, and that definitely was hard, because I genuinely felt so sick, and I was in a lot of pain," she says. "It definitely hurt me, physically and emotionally."

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Although POTS isn’t life-threatening, it can greatly interfere with everyday life and tasks. There is also no cure for POTS. Instead, healthcare providers will manage the condition with medications for specific symptoms and lifestyle changes like physical activity and diet.

Sadie said when she first began experiencing symptoms in 2020, "every time I stood up, I just felt like my whole world was just about to go crashing down and my vision would get blurry."

Applegate said at first she didn't realize what Sadie was dealing with. "I feel very guilty because... I didn't really understand what was happening with her," she said. "I feel so horrible that we didn't pay attention to it...I'd never heard of this either. I'm so sorry, Sadie Grace,"

Part of the reason Applegate says she didn't understand her daughter's struggles was because she didn't see the symptoms at home. "At home, you were fine," said Applegate, who compared her daughter's experience with her own as someone living with multiple sclerosis. "It's kind of like us. We get out in the world and the stresses and the anxiety of the world bring upon our symptoms much worse than they would be if we were in the safety and the coolness of our own homes."

And she praised her daughter for sharing her condition so openly.  "I hate it for you, my darling...and I'm here for you and I believe you," she said. "And thank you for bringing this to light and bringing awareness. A lot of people don't know about this."

Sadie also said on the show that she suffers from misophonia, which causes intense, overwhelming emotional and physical reactions to certain sounds. "My two worst are breathing and chewing," she said.

However, she admitted that navigating her own health battles has helped her empathize with Applegate’s journey with MS after the actress was diagnosed in 2021.

"When my mom's like, 'I'm in pain right now. I'm having tremors.' If I didn't have [POTS], I probably would be like...I don't know what you're talking about. But I actually have tremors from POTS," Sadie said. "It's definitely a lot easier to understand what she's going through when I have something I'm going through as well."