Adderall is a stimulant medication used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy. While some people report feeling more alert and focused when taking Adderall, others may experience side effects like headaches, nervousness, restlessness, and insomnia. There are some reports of Adderall causing “brain fog,” which is a feeling of mental confusion, forgetfulness, or lack of mental clarity. However, it is important to note that everyone’s experience with Adderall can be different and that any concerns about side effects or effectiveness should be discussed with a doctor or healthcare provider.