Re-Lyte Pre-Workout contains 150 mg of caffeine per serving, so it could keep you awake at night depending on your caffeine sensitivity.
Each serving of Re-Lyte Pre-Workout contains about 150 mg of caffeine. A cup of coffee contains about 95 mg of caffeine. So you're getting a hefty dose of caffeine (and energy) when you take a serving of Pre-Workout.
Whether that keeps you awake at night depends on how you respond to caffeine. Caffeine sensitivity and tolerance vary a lot from person to person, and this variation carries over to how caffeine influences sleep.
Some people are able to drink cup after cup of coffee in the evening and still sleep like a baby. Others can't sleep if a drop of coffee touches their tongue after 4 pm. If you know that drinking caffeinated beverages in the evening interferes with your sleep then we'd recommend only using Pre-Workout for daytime workouts.