For severe adhd which is life-threatening or threatens safety. Climbing on shelves and over fences, running into streets, being aggressive, strong emotions, having (abnormal) tantrums frequently, not paying any attention whatsoever, getting into fights due to impulsivity, and all of these symptoms not being resolved by counselling and good parenting, then medication may be necessary
With medication there should still be counselling and good parenting, tailored to the child's needs.
However as children's brains are still developing and stimulant medications can potentially be harmful, we need to be VERY careful about it.
Stimulant medications aren't the only thing, other medications may be useful and perhaps more useful, depends on the child, their presentation may help determine which medication may be more useful
I do not think that young children should be prescribed stimulants for ADD/ADHD. I think that ADD/ADHD is something that was invented by the medical companies to sell prescription drugs. That is the reason why it is so overtly prescribed and diagnosed. I think that the medical field should do away with the disease.
Some of what gets diagnosed as ADD or ADHD is actually "Poor Teaching Syndrome." When our schools give kids a large number of worksheets to be done while sitting at a desk for two hours, a task many adults would find onerous, it is not surprising that some of the brighter children rebel. There are children who benefit from medication for ADD or ADHD, but we need to do a better job differentiating between the children who truly need it and the ones who need teachers with good common sense.
Young children should not be prescribed stimulants for ADD/ADHD. This is because children should not be hopped up or dumbed down on chemicals the majority of the time. Only in rare cases should this be done. These medications have bad side-effects. If kids went outside to play more or had more physical activity, they would be prescribed much less mood-altering drugs.
I do not think young children should be prescribed stimulants for ADD or ADHD. I think our problem is how boring school is and the way we teach our children. We make them sit there all day long absorbing information in the most boring ways possible, and it's not tailored to each individual student.