nightwarea “digital therapeutic system” that works in conjunction with apple inc‘s AAPL smart watch and iPhonehelps veterans and active service members who suffer from Post Traumatic Stress Disorder or PTSD deal with nightmares and get a good night’s sleep.

What happened: Available by prescription, it is the first and only digital therapeutic specifically designed to treat nightmares and has received FDA approval.

NightWare uses information from the Apple Watch’s heart rate monitor, accelerometer, and gyroscope to detect a nightmare. When a person is having a nightmare, the platform sends haptic feedback and generates gentle pulses on the user’s wrist to cleverly interrupt the nightmare without affecting their sleep.

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Apple told the story of Robert Guithues, an Army veteran who has served for over two decades and suffers from PTSD. He used to wake up at night thinking he was back in the burning oil fields outside of Baghdad, but everything changed when he started using NightWare.

“Some of the most terrifying sights I’ve ever seen played over and over again, but once I started using NightWare, they stopped,” Guithues said.

Why it matters: NightWare has been prescribed to 400 patients in the US to date, 98% of whom are active military or veterans. according to to AppleInsider.

According to a peer-reviewed Journal of Clinical Sleep Medicine, participants using NightWare had significantly better self-supported sleep than their peers 50% of the time.

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