For people struggling with post-traumatic stress disorder, or PTSD, nighttime can be particularly scary. The need to sleep is overwhelming, but that’s when nightmares emerge, snapping them awake and triggering anxieties and fear.

Now, the Food and Drug Administration has authorized a smartwatch app called NightWare that aims to take back the night.

NightWare creates a sleep profile for the wearer based on body movements and heart rate. Sensors in the watch monitor the person’s sleep and send data to the manufacturer’s server when a nightmare begins. The watch then vibrates subtly, just enough to disrupt the nightmare while not fully waking the user.

According to a NightWare executive, a college student looking to help his father, an Army veteran diagnosed with PTSD, developed the concept. The technology is similar to that of service dogs that wake their owners during nightmares by licking their face or turning on the lights. The device takes it to another level by arousing users just enough to ease them out of the nightmare without waking them up.

The FDA approved the system after a 30-day trial in which people wearing the vibrating device showed significantly improved scores on a sleep quality scale compared to those who wore inert devices.

People with PTSD are often sleep-deprived, and severe nightmares have been linked to higher rates of suicide, heart disease and other adverse health conditions. There are medications that help with these disorders, and NightWare is intended to be used along with the drugs.

This breakthrough technology may prove to be a game-changer for those just hoping for something many of us take for granted: a good night’s sleep.