In the early days of the war, Sofia Tsarenko, 22, would drink with friends in Ukraine to relax. She soon found that without a bottle of wine, her anxiety would become so unbearable that she could not fall asleep.

But as the war dragged on, Ms. Tsarenko said, her anxiety got worse and she became increasingly irritable. The wine stopped helping. It was only when she tried sleeping pills and antidepressants that she was able to get some relief.

“I felt like angels were taking me to sleep,” said Ms. Tsarenko, who lives in the eastern city of Dnipro.

Russia’s full-scale invasion of Ukraine has killed thousands of people and wounded tens of thousands more. But the toll is not just physical: Three years of war have wrought immense psychological harm. Now sleep deprivation has become a national health crisis in Ukraine, experts and psychologists say, citing near-nightly drone attacks as a key driver.

In towns and cities across the country each night, Ukrainians lie awake in bed, listening and waiting for the sounds of Russian drones buzzing like lawn mowers in the sky, then for the explosions. Drone strikes have only intensified since U.S.-mediated peace talks began, according to Ukrainian officials. And Russia appears to be increasingly targeting urban areas, as with a huge and deadly strike in Kyiv on Thursday, adding to civilians’ anxiety and causing more sleepless nights.

Chronic sleep deprivation has a profound impact on psychological well-being, according to experts. Sometimes referred to as “sleep debt,” it can cause anxiety and irritability, along with depression and other more severe mental health concerns, they say.