Prolax syrup is an over-the-counter medication used to reduce the time needed to fall asleep. It is usually taken before bedtime. It may also be taken during the day if you feel anxious or have trouble sleeping. It is a sugar-free and calorie-free liquid medication used to relieve fever symptoms, such as headaches, body aches, and pain. It comes in various flavors, such as mango, grape, and strawberry.