Hello Dear. Headache and heaviness of legs is due to side effect of Adderall. Adderall contains a combination of amphetamine and dextroamphetamine. Amphetamine and dextroamphetamine are central nervous system stimulants that affect chemicals in the brain and nerves that contribute to hyperactivity and impulse control. Adderall is used to treat narcolepsy and attention deficit hyperactivity disorder (ADHD). Adderall can affect growth in children. Tell your doctor if your child is not growing at a normal rate while using this medicine. Stop using this medicine and call your doctor at once if you have: 1. chest pain, trouble breathing, feeling like you might pass out; 2. hallucinations (seeing or hearing things that are not real), new behavior 3. problems, aggression, hostility, paranoia; 4. a seizure (convulsions); 5. numbness, pain, cold feeling, unexplained wounds, or skin color changes (pale, red, or blue appearance) in your fingers or toes; 6. muscle twitches (tics); 7. changes in your vision; or 8. unexplained muscle pain, tenderness, or weakness (especially if you also have fever, unusual tiredness, and dark colored urine). Common Adderall side effects may include: 1. stomach pain, loss of appetite; 2. weight loss; 3. mood changes, feeling nervous; 4. fast heart rate; 5. headache, dizziness; 6. sleep problems (insomnia); or 7. dry mouth. Kindly discuss with your doctor if the drug has to be changed or the benefit of taking drug outweighs side effect. Hope i have answered your question. Feel free to contact me if you have any more questions. I ll be glad to help you. All the best With warm regards Dr Sanjay Kini