Concerta is a brand name for a medication that contains methylphenidate, which is primarily used to treat attention deficit hyperactivity disorder (ADHD) in children and adults. The 27 mg formulation is an extended-release version that helps manage symptoms throughout the day. It works by increasing levels of certain neurotransmitters in the brain, which helps improve focus, attention, and impulse control. It's usually taken once daily in the morning, as it can interfere with sleep if taken later in the day.