Children and adolescents who take medication for attention-deficit hyperactivity disorder (ADHD) may be at a risk of reduced bone density warns a study. The results indicated that kids on ADHD medication had lower bone mineral density in the femur femoral neck and lumbar spine. The medications can cause gastrointestinal problems such as decreased appetite and stomach upset which may result in poor nutrition and reduced calcium intake. The drugs also may diminish bone density because they alter the sympathetic nervous system which plays an important role in bone remodelling or regeneration. This is an important step in understanding a medication