Amphetamine-type drugs, such as lisdexamfetamine, were found to be most effective for treating ADHD symptoms in adults. This finding is based on pooling the results of previously published studies. It's not the result of a new experiment. But the study did not say drugs are the best treatment for ADHD and more children should be provided with them, as the headlines imply. Drugs are effective in many cases, but they also have many side effects, such as weight loss, increased blood pressure and problems sleeping, which can be difficult to manage.